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*       www.FindStat.org - The Combinatorial Statistic Finder               *
*                                                                           *
*       Copyright (C) 2019 The FindStatCrew <info@findstat.org>             *
*                                                                           *
*    This information is distributed in the hope that it will be useful,    *
*    but WITHOUT ANY WARRANTY; without even the implied warranty of         *
*    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.                   *
*****************************************************************************

-----------------------------------------------------------------------------
Statistic identifier: St000826

-----------------------------------------------------------------------------
Collection: Binary words

-----------------------------------------------------------------------------
Description: The stopping time of the decimal representation of the binary word for the 3x+1 problem.

Prepend $1$ to the binary word, interpret it as a positive number, and count the number of halving and tripling steps needed to reach $1$.

-----------------------------------------------------------------------------
References: [1]   [[wikipedia:3x_+_1_problem]]

-----------------------------------------------------------------------------
Code:
def statistic(w):
    return collatz(Integer("0b1" + str(w)))

@cached_function
def collatz(n):
    if n == 1:
        return 0
    elif is_even(n):
        return 1+collatz(n//2)
    else:
        return 1+collatz(3*n+1)


-----------------------------------------------------------------------------
Statistic values:

0          => 1
1          => 7
00         => 2
01         => 5
10         => 8
11         => 16
000        => 3
001        => 19
010        => 6
011        => 14
100        => 9
101        => 9
110        => 17
111        => 17
0000       => 4
0001       => 12
0010       => 20
0011       => 20
0100       => 7
0101       => 7
0110       => 15
0111       => 15
1000       => 10
1001       => 23
1010       => 10
1011       => 111
1100       => 18
1101       => 18
1110       => 18
1111       => 106
00000      => 5
00001      => 26
00010      => 13
00011      => 13
00100      => 21
00101      => 21
00110      => 21
00111      => 34
01000      => 8
01001      => 109
01010      => 8
01011      => 29
01100      => 16
01101      => 16
01110      => 16
01111      => 104
10000      => 11
10001      => 24
10010      => 24
10011      => 24
10100      => 11
10101      => 11
10110      => 112
10111      => 112
11000      => 19
11001      => 32
11010      => 19
11011      => 32
11100      => 19
11101      => 19
11110      => 107
11111      => 107
000000     => 6
000001     => 27
000010     => 27
000011     => 27
000100     => 14
000101     => 14
000110     => 14
000111     => 102
001000     => 22
001001     => 115
001010     => 22
001011     => 14
001100     => 22
001101     => 22
001110     => 35
001111     => 35
010000     => 9
010001     => 22
010010     => 110
010011     => 110
010100     => 9
010101     => 9
010110     => 30
010111     => 30
011000     => 17
011001     => 30
011010     => 17
011011     => 92
011100     => 17
011101     => 17
011110     => 105
011111     => 105
100000     => 12
100001     => 118
100010     => 25
100011     => 25
100100     => 25
100101     => 25
100110     => 25
100111     => 87
101000     => 12
101001     => 38
101010     => 12
101011     => 100
101100     => 113
101101     => 113
101110     => 113
101111     => 69
110000     => 20
110001     => 12
110010     => 33
110011     => 33
110100     => 20
110101     => 20
110110     => 33
110111     => 33
111000     => 20
111001     => 95
111010     => 20
111011     => 46
111100     => 108
111101     => 108
111110     => 108
111111     => 46
0000000    => 7
0000001    => 121
0000010    => 28
0000011    => 28
0000100    => 28
0000101    => 28
0000110    => 28
0000111    => 41
0001000    => 15
0001001    => 90
0001010    => 15
0001011    => 41
0001100    => 15
0001101    => 15
0001110    => 103
0001111    => 103
0010000    => 23
0010001    => 116
0010010    => 116
0010011    => 116
0010100    => 23
0010101    => 23
0010110    => 15
0010111    => 15
0011000    => 23
0011001    => 36
0011010    => 23
0011011    => 85
0011100    => 36
0011101    => 36
0011110    => 36
0011111    => 54
0100000    => 10
0100001    => 98
0100010    => 23
0100011    => 23
0100100    => 111
0100101    => 111
0100110    => 111
0100111    => 67
0101000    => 10
0101001    => 49
0101010    => 10
0101011    => 124
0101100    => 31
0101101    => 31
0101110    => 31
0101111    => 80
0110000    => 18
0110001    => 31
0110010    => 31
0110011    => 31
0110100    => 18
0110101    => 18
0110110    => 93
0110111    => 93
0111000    => 18
0111001    => 44
0111010    => 18
0111011    => 44
0111100    => 106
0111101    => 106
0111110    => 106
0111111    => 44
1000000    => 13
1000001    => 119
1000010    => 119
1000011    => 119
1000100    => 26
1000101    => 26
1000110    => 26
1000111    => 119
1001000    => 26
1001001    => 18
1001010    => 26
1001011    => 39
1001100    => 26
1001101    => 26
1001110    => 88
1001111    => 88
1010000    => 13
1010001    => 39
1010010    => 39
1010011    => 39
1010100    => 13
1010101    => 13
1010110    => 101
1010111    => 101
1011000    => 114
1011001    => 26
1011010    => 114
1011011    => 52
1011100    => 114
1011101    => 114
1011110    => 70
1011111    => 70
1100000    => 21
1100001    => 52
1100010    => 13
1100011    => 13
1100100    => 34
1100101    => 34
1100110    => 34
1100111    => 127
1101000    => 21
1101001    => 83
1101010    => 21
1101011    => 127
1101100    => 34
1101101    => 34
1101110    => 34
1101111    => 52
1110000    => 21
1110001    => 21
1110010    => 96
1110011    => 96
1110100    => 21
1110101    => 21
1110110    => 47
1110111    => 47
1111000    => 109
1111001    => 47
1111010    => 109
1111011    => 65
1111100    => 109
1111101    => 109
1111110    => 47
1111111    => 47
00000000   => 8
00000001   => 122
00000010   => 122
00000011   => 122
00000100   => 29
00000101   => 29
00000110   => 29
00000111   => 78
00001000   => 29
00001001   => 122
00001010   => 29
00001011   => 21
00001100   => 29
00001101   => 29
00001110   => 42
00001111   => 42
00010000   => 16
00010001   => 29
00010010   => 91
00010011   => 91
00010100   => 16
00010101   => 16
00010110   => 42
00010111   => 42
00011000   => 16
00011001   => 42
00011010   => 16
00011011   => 60
00011100   => 104
00011101   => 104
00011110   => 104
00011111   => 42
00100000   => 24
00100001   => 29
00100010   => 117
00100011   => 117
00100100   => 117
00100101   => 117
00100110   => 117
00100111   => 55
00101000   => 24
00101001   => 73
00101010   => 24
00101011   => 117
00101100   => 16
00101101   => 16
00101110   => 16
00101111   => 42
00110000   => 24
00110001   => 37
00110010   => 37
00110011   => 37
00110100   => 24
00110101   => 24
00110110   => 86
00110111   => 86
00111000   => 37
00111001   => 130
00111010   => 37
00111011   => 37
00111100   => 37
00111101   => 37
00111110   => 55
00111111   => 55
01000000   => 11
01000001   => 24
01000010   => 99
01000011   => 99
01000100   => 24
01000101   => 24
01000110   => 24
01000111   => 143
01001000   => 112
01001001   => 50
01001010   => 112
01001011   => 24
01001100   => 112
01001101   => 112
01001110   => 68
01001111   => 68
01010000   => 11
01010001   => 112
01010010   => 50
01010011   => 50
01010100   => 11
01010101   => 11
01010110   => 125
01010111   => 125
01011000   => 32
01011001   => 125
01011010   => 32
01011011   => 125
01011100   => 32
01011101   => 32
01011110   => 81
01011111   => 81
01100000   => 19
01100001   => 125
01100010   => 32
01100011   => 32
01100100   => 32
01100101   => 32
01100110   => 32
01100111   => 50
01101000   => 19
01101001   => 45
01101010   => 19
01101011   => 45
01101100   => 94
01101101   => 94
01101110   => 94
01101111   => 45
01110000   => 19
01110001   => 19
01110010   => 45
01110011   => 45
01110100   => 19
01110101   => 19
01110110   => 45
01110111   => 45
01111000   => 107
01111001   => 63
01111010   => 107
01111011   => 58
01111100   => 107
01111101   => 107
01111110   => 45
01111111   => 45
10000000   => 14
10000001   => 32
10000010   => 120
10000011   => 120
10000100   => 120
10000101   => 120
10000110   => 120
10000111   => 120
10001000   => 27
10001001   => 58
10001010   => 27
10001011   => 76
10001100   => 27
10001101   => 27
10001110   => 120
10001111   => 120
10010000   => 27
10010001   => 19
10010010   => 19
10010011   => 19
10010100   => 27
10010101   => 27
10010110   => 40
10010111   => 40
10011000   => 27
10011001   => 40
10011010   => 27
10011011   => 133
10011100   => 89
10011101   => 89
10011110   => 89
10011111   => 133
10100000   => 14
10100001   => 133
10100010   => 40
10100011   => 40
10100100   => 40
10100101   => 40
10100110   => 40
10100111   => 32
10101000   => 14
10101001   => 58
10101010   => 14
10101011   => 53
10101100   => 102
10101101   => 102
10101110   => 102
10101111   => 40
10110000   => 115
10110001   => 27
10110010   => 27
10110011   => 27
10110100   => 115
10110101   => 115
10110110   => 53
10110111   => 53
10111000   => 115
10111001   => 27
10111010   => 115
10111011   => 53
10111100   => 71
10111101   => 71
10111110   => 71
10111111   => 97
11000000   => 22
11000001   => 115
11000010   => 53
11000011   => 53
11000100   => 14
11000101   => 14
11000110   => 14
11000111   => 40
11001000   => 35
11001001   => 128
11001010   => 35
11001011   => 128
11001100   => 35
11001101   => 35
11001110   => 128
11001111   => 128
11010000   => 22
11010001   => 35
11010010   => 84
11010011   => 84
11010100   => 22
11010101   => 22
11010110   => 128
11010111   => 128
11011000   => 35
11011001   => 35
11011010   => 35
11011011   => 27
11011100   => 35
11011101   => 35
11011110   => 53
11011111   => 53
11100000   => 22
11100001   => 48
11100010   => 22
11100011   => 22
11100100   => 97
11100101   => 97
11100110   => 97
11100111   => 141
11101000   => 22
11101001   => 48
11101010   => 22
11101011   => 141
11101100   => 48
11101101   => 48
11101110   => 48
11101111   => 97
11110000   => 110
11110001   => 22
11110010   => 48
11110011   => 48
11110100   => 110
11110101   => 110
11110110   => 66
11110111   => 66
11111000   => 110
11111001   => 61
11111010   => 110
11111011   => 35
11111100   => 48
11111101   => 48
11111110   => 48
11111111   => 61
000000000  => 9
000000001  => 35
000000010  => 123
000000011  => 123
000000100  => 123
000000101  => 123
000000110  => 123
000000111  => 61
000001000  => 30
000001001  => 123
000001010  => 30
000001011  => 123
000001100  => 30
000001101  => 30
000001110  => 79
000001111  => 79
000010000  => 30
000010001  => 30
000010010  => 123
000010011  => 123
000010100  => 30
000010101  => 30
000010110  => 22
000010111  => 22
000011000  => 30
000011001  => 22
000011010  => 30
000011011  => 48
000011100  => 43
000011101  => 43
000011110  => 43
000011111  => 136
000100000  => 17
000100001  => 43
000100010  => 30
000100011  => 30
000100100  => 92
000100101  => 92
000100110  => 92
000100111  => 43
000101000  => 17
000101001  => 136
000101010  => 17
000101011  => 30
000101100  => 43
000101101  => 43
000101110  => 43
000101111  => 87
000110000  => 17
000110001  => 43
000110010  => 43
000110011  => 43
000110100  => 17
000110101  => 17
000110110  => 61
000110111  => 61
000111000  => 105
000111001  => 56
000111010  => 105
000111011  => 30
000111100  => 105
000111101  => 105
000111110  => 43
000111111  => 43
001000000  => 25
001000001  => 30
001000010  => 30
001000011  => 30
001000100  => 118
001000101  => 118
001000110  => 118
001000111  => 30
001001000  => 118
001001001  => 56
001001010  => 118
001001011  => 118
001001100  => 118
001001101  => 118
001001110  => 56
001001111  => 56
001010000  => 25
001010001  => 74
001010010  => 74
001010011  => 74
001010100  => 25
001010101  => 25
001010110  => 118
001010111  => 118
001011000  => 17
001011001  => 56
001011010  => 17
001011011  => 69
001011100  => 17
001011101  => 17
001011110  => 43
001011111  => 43
001100000  => 25
001100001  => 131
001100010  => 38
001100011  => 38
001100100  => 38
001100101  => 38
001100110  => 38
001100111  => 69
001101000  => 25
001101001  => 131
001101010  => 25
001101011  => 131
001101100  => 87
001101101  => 87
001101110  => 87
001101111  => 131
001110000  => 38
001110001  => 25
001110010  => 131
001110011  => 131
001110100  => 38
001110101  => 38
001110110  => 38
001110111  => 38
001111000  => 38
001111001  => 30
001111010  => 38
001111011  => 30
001111100  => 56
001111101  => 56
001111110  => 56
001111111  => 131
010000000  => 12
010000001  => 51
010000010  => 25
010000011  => 25
010000100  => 100
010000101  => 100
010000110  => 100
010000111  => 38
010001000  => 25
010001001  => 144
010001010  => 25
010001011  => 100
010001100  => 25
010001101  => 25
010001110  => 144
010001111  => 144
010010000  => 113
010010001  => 51
010010010  => 51
010010011  => 51
010010100  => 113
010010101  => 113
010010110  => 25
010010111  => 25
010011000  => 113
010011001  => 51
010011010  => 113
010011011  => 144
010011100  => 69
010011101  => 69
010011110  => 69
010011111  => 95
010100000  => 12
010100001  => 64
010100010  => 113
010100011  => 113
010100100  => 51
010100101  => 51
010100110  => 51
010100111  => 64
010101000  => 12
010101001  => 64
010101010  => 12
010101011  => 38
010101100  => 126
010101101  => 126
010101110  => 126
010101111  => 38
010110000  => 33
010110001  => 126
010110010  => 126
010110011  => 126
010110100  => 33
010110101  => 33
010110110  => 126
010110111  => 126
010111000  => 33
010111001  => 126
010111010  => 33
010111011  => 64
010111100  => 82
010111101  => 82
010111110  => 82
010111111  => 170
011000000  => 20
011000001  => 33
011000010  => 126
011000011  => 126
011000100  => 33
011000101  => 33
011000110  => 33
011000111  => 64
011001000  => 33
011001001  => 25
011001010  => 33
011001011  => 25
011001100  => 33
011001101  => 33
011001110  => 51
011001111  => 51
011010000  => 20
011010001  => 46
011010010  => 46
011010011  => 46
011010100  => 20
011010101  => 20
011010110  => 46
011010111  => 46
011011000  => 95
011011001  => 33
011011010  => 95
011011011  => 139
011011100  => 95
011011101  => 95
011011110  => 46
011011111  => 46
011100000  => 20
011100001  => 139
011100010  => 20
011100011  => 20
011100100  => 46
011100101  => 46
011100110  => 46
011100111  => 95
011101000  => 20
011101001  => 90
011101010  => 20
011101011  => 46
011101100  => 46
011101101  => 46
011101110  => 46
011101111  => 139
011110000  => 108
011110001  => 20
011110010  => 64
011110011  => 64
011110100  => 108
011110101  => 108
011110110  => 59
011110111  => 59
011111000  => 108
011111001  => 33
011111010  => 108
011111011  => 152
011111100  => 46
011111101  => 46
011111110  => 46
011111111  => 59
100000000  => 15
100000001  => 33
100000010  => 33
100000011  => 33
100000100  => 121
100000101  => 121
100000110  => 121
100000111  => 152
100001000  => 121
100001001  => 33
100001010  => 121
100001011  => 59
100001100  => 121
100001101  => 121
100001110  => 121
100001111  => 121
100010000  => 28
100010001  => 121
100010010  => 59
100010011  => 59
100010100  => 28
100010101  => 28
100010110  => 77
100010111  => 77
100011000  => 28
100011001  => 77
100011010  => 28
100011011  => 103
100011100  => 121
100011101  => 121
100011110  => 121
100011111  => 72
100100000  => 28
100100001  => 59
100100010  => 20
100100011  => 20
100100100  => 20
100100101  => 20
100100110  => 20
100100111  => 72
100101000  => 28
100101001  => 46
100101010  => 28
100101011  => 134
100101100  => 41
100101101  => 41
100101110  => 41
100101111  => 134
100110000  => 28
100110001  => 41
100110010  => 41
100110011  => 41
100110100  => 28
100110101  => 28
100110110  => 134
100110111  => 134
100111000  => 90
100111001  => 134
100111010  => 90
100111011  => 41
100111100  => 90
100111101  => 90
100111110  => 134
100111111  => 134
101000000  => 15
101000001  => 28
101000010  => 134
101000011  => 134
101000100  => 41
101000101  => 41
101000110  => 41
101000111  => 85
101001000  => 41
101001001  => 41
101001010  => 41
101001011  => 41
101001100  => 41
101001101  => 41
101001110  => 33
101001111  => 33
101010000  => 15
101010001  => 59
101010010  => 59
101010011  => 59
101010100  => 15
101010101  => 15
101010110  => 54
101010111  => 54
101011000  => 103
101011001  => 28
101011010  => 103
101011011  => 147
101011100  => 103
101011101  => 103
101011110  => 41
101011111  => 41
101100000  => 116
101100001  => 147
101100010  => 28
101100011  => 28
101100100  => 28
101100101  => 28
101100110  => 28
101100111  => 178
101101000  => 116
101101001  => 147
101101010  => 116
101101011  => 28
101101100  => 54
101101101  => 54
101101110  => 54
101101111  => 147
101110000  => 116
101110001  => 116
101110010  => 28
101110011  => 28
101110100  => 116
101110101  => 116
101110110  => 54
101110111  => 54
101111000  => 72
101111001  => 147
101111010  => 72
101111011  => 46
101111100  => 72
101111101  => 72
101111110  => 98
101111111  => 98
110000000  => 23
110000001  => 67
110000010  => 116
110000011  => 116
110000100  => 54
110000101  => 54
110000110  => 54
110000111  => 116
110001000  => 15
110001001  => 67
110001010  => 15
110001011  => 54
110001100  => 15
110001101  => 15
110001110  => 41
110001111  => 41
110010000  => 36
110010001  => 129
110010010  => 129
110010011  => 129
110010100  => 36
110010101  => 36
110010110  => 129
110010111  => 129
110011000  => 36
110011001  => 129
110011010  => 36
110011011  => 67
110011100  => 129
110011101  => 129
110011110  => 129
110011111  => 116
110100000  => 23
110100001  => 129
110100010  => 36
110100011  => 36
110100100  => 85
110100101  => 85
110100110  => 85
110100111  => 129
110101000  => 23
110101001  => 173
110101010  => 23
110101011  => 85
110101100  => 129
110101101  => 129
110101110  => 129
110101111  => 36
110110000  => 36
110110001  => 36
110110010  => 36
110110011  => 36
110110100  => 36
110110101  => 36
110110110  => 28
110110111  => 28
110111000  => 36
110111001  => 28
110111010  => 36
110111011  => 28
110111100  => 54
110111101  => 54
110111110  => 54
110111111  => 129
111000000  => 23
111000001  => 49
111000010  => 49
111000011  => 49
111000100  => 23
111000101  => 23
111000110  => 23
111000111  => 142
111001000  => 98
111001001  => 49
111001010  => 98
111001011  => 36
111001100  => 98
111001101  => 98
111001110  => 142
111001111  => 142
111010000  => 23
111010001  => 98
111010010  => 49
111010011  => 49
111010100  => 23
111010101  => 23
111010110  => 142
111010111  => 142
111011000  => 49
111011001  => 23
111011010  => 49
111011011  => 36
111011100  => 49
111011101  => 49
111011110  => 98
111011111  => 98
111100000  => 111
111100001  => 93
111100010  => 23
111100011  => 23
111100100  => 49
111100101  => 49
111100110  => 49
111100111  => 49
111101000  => 111
111101001  => 142
111101010  => 111
111101011  => 41
111101100  => 67
111101101  => 67
111101110  => 67
111101111  => 93
111110000  => 111
111110001  => 111
111110010  => 62
111110011  => 62
111110100  => 111
111110101  => 111
111110110  => 36
111110111  => 36
111111000  => 49
111111001  => 155
111111010  => 49
111111011  => 62
111111100  => 49
111111101  => 49
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0000000000 => 10
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0010100000 => 26
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0000001110 => 62
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0000000100 => 124
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0000000101 => 124
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0001010000 => 18
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0010000000 => 26
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0010000101 => 31
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0000101011 => 62
0001000111 => 75
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0001001010 => 93
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0001000101 => 31
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0001001100 => 93
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0010010000 => 119
0001010010 => 137
0001000000 => 18
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0010101001 => 101
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0001001101 => 93
0001010001 => 93
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0001111011 => 57
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0001011000 => 44
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0010000110 => 31
0000110000 => 31
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0010100011 => 75
0010100001 => 150
0000111000 => 44
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0000010000 => 31
0000101001 => 75
0010100010 => 75
0010001001 => 181
0010000011 => 31
0010001010 => 119
0001110000 => 106

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Created: May 30, 2017 at 22:00 by Martin Rubey

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Last Updated: May 30, 2017 at 22:00 by Martin Rubey