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A372129
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Lexicographically earliest sequence of distinct nonnegative integers such that for any n >= 0, the binary expansions of a(n), a(2*n+1) and a(2*n+2) have distinct 1's.
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5
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0, 1, 2, 4, 8, 5, 16, 3, 24, 6, 17, 10, 32, 7, 40, 12, 48, 33, 64, 9, 80, 14, 96, 20, 65, 11, 68, 56, 128, 18, 69, 19, 160, 13, 66, 22, 72, 15, 144, 34, 84, 35, 132, 49, 192, 21, 130, 41, 194, 26, 36, 52, 256, 25, 162, 67, 260, 23, 104, 37, 136, 42, 272, 44
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OFFSET
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0,3
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COMMENTS
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This sequence is a permutation of the nonnegative integers with inverse A372131:
- for any k >= 0, the first term >= 2^k is precisely 2^k,
- all powers of 2 appear in the sequence, in increasing order,
- for any v >= 0, every power of 2 that doesn't appear in the binary expansion of v provides an opportunity to select v later, and eventually v will appear in the sequence.
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LINKS
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FORMULA
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a(n) AND a(2*n+1) = a(n) AND a(2*n+2) = a(2*n+1) AND a(2*n+2) = 0 for any n >= 0 (where AND denotes the bitwise AND operator).
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EXAMPLE
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The first terms, arranged alongside a binary tree where siblings have distinct binary 1's and parent and children have distinct binary 1's, are:
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.-------0-------.
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.---1---. .---2---.
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.-4-. .-8-. .-5-. .16-.
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3 24 6 17 10 32 7 40
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PROG
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(PARI) \\ See Links section.
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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STATUS
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approved
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