cp's OEIS Frontend

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.

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A386249 a(n) is the Hamming weight of A161792(n).

Original entry on oeis.org

1, 1, 1, 1, 2, 1, 1, 2, 1, 1, 2, 1, 1, 2, 6, 1, 1, 2, 1, 1, 2, 1, 1, 2, 6, 1, 1, 2, 1, 1, 2, 1, 1, 2, 6, 1, 14, 1, 2, 15, 1, 1, 2, 1, 1, 2, 6, 1, 1, 2, 1, 1, 2, 1, 1, 2, 6, 1, 1, 2, 1, 14, 1, 2, 1, 15, 1, 2, 6, 1, 1, 2, 1, 1, 2, 1, 19, 1, 2, 6, 1, 1, 2, 1, 1, 2
Offset: 1

Views

Author

Rémy Sigrist, Jul 16 2025

Keywords

Comments

All terms appear infinitely many times: for any n > 0, A161792(n)*2^a(n) also belongs to A161792, say it equals A161792(m) for some m > n, so a(n) = a(m), and we can find as many other occurrences of a(n) as we want.

Examples

			a(35) = A000120(2985984) = 6.
		

Crossrefs

Programs

  • PARI
    { for (n = 1, oo, if (ispower(n, h = hammingweight(n)), print1 (h", "));); }

Formula

a(n) = A000120(A161792(n)).

Extensions

a(65) and beyond from Michael S. Branicky, Jul 21 2025 using A161792

A386290 a(1) = a(2) = 1, and for n > 2, a(n) is the unique k such that A256590(n) = A000120(A256590(n))^k.

Original entry on oeis.org

1, 1, 4, 4, 5, 5, 6, 5, 8, 8, 8, 10, 10, 10, 11, 12, 13, 15, 13, 16, 17, 14, 17, 19, 18, 18, 19, 26, 20, 23, 23, 23, 26, 26, 25, 25, 27, 27, 35, 30, 31, 31, 31, 32, 33, 34, 34, 35, 33, 39, 35, 36, 40, 38, 39, 40, 42, 42, 43, 42, 51, 44, 47, 44, 59, 47, 50, 48
Offset: 1

Views

Author

Rémy Sigrist, Jul 17 2025

Keywords

Examples

			For n = 8: A256590(8) = 59049 = 9^5 = A000120(59049)^5, so a(8) = 5.
		

Crossrefs

Programs

  • PARI
    \\ See Links section.

Formula

A256590(n) = A386289(n)^a(n).
Showing 1-2 of 2 results.