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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

User: Alexander Khudyakov

Alexander Khudyakov's wiki page.

Alexander Khudyakov has authored 1 sequences.

A365396 Inverse permutation to A243571.

Original entry on oeis.org

1, 2, 3, 4, 5, 6, 8, 7, 9, 10, 13, 11, 14, 15, 21, 12, 16, 17, 22, 18, 23, 24, 34, 19, 25, 26, 35, 27, 36, 37, 55, 20, 28, 29, 38, 30, 39, 40, 56, 31, 41, 42, 57, 43, 58, 59, 89, 32, 44, 45, 60, 46, 61, 62, 90, 47, 63, 64, 91, 65, 92, 93, 144, 33, 48, 49, 66
Offset: 1

Author

Alexander Khudyakov, Sep 03 2023

Keywords

Programs

  • PARI
    a(n) = my(L = logint(n, 2), wt = hammingweight(n), A = L + wt, m = 0); fibonacci(A+1) + sum(i=1, L, binomial(i-1, A-i)) + sum(j=0, L-1, if(bittest(n, j), m++; binomial(j, m)))

Formula

a(n) = A000045(b(n) + 1) + Sum_{i=1..A000523(n)} binomial(i-1, b(n) - i) + Sum_{j=1..A000120(n) - 1} binomial(A133457(n, j), j) where b(n) = A056792(n).