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.

A374114 Numbers k such that A113177(k) and A276085(k) are both even, where A113177 and A276085 are fully additive with a(p) = Fibonacci(p) and a(p) = p#/p, respectively.

Original entry on oeis.org

1, 3, 4, 9, 12, 16, 25, 27, 35, 36, 48, 49, 55, 64, 65, 75, 77, 81, 85, 91, 95, 100, 105, 108, 115, 119, 121, 133, 140, 143, 144, 145, 147, 155, 161, 165, 169, 185, 187, 192, 195, 196, 203, 205, 209, 215, 217, 220, 221, 225, 231, 235, 243, 247, 253, 255, 256, 259, 260, 265, 273, 285, 287, 289, 295, 299, 300, 301, 305
Offset: 1

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Author

Antti Karttunen, Jun 29 2024

Keywords

Comments

Numbers whose 2-adic valuation (A007814) is even, and the number of the prime factors (with multiplicity, A001222) and the 3-adic valuation (A007949) have the same parity.
A multiplicative semigroup: if m and n are in the sequence, then so is m*n.

Crossrefs

Intersection of A003159 and A373586.
Indices of even terms in A374112.
Cf. A001222, A007814, A007949, A113177, A276085, A374113 (characteristic function), A374115 (complement).

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