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.

A373373 Numbers k for which both A001414(k) and A276085(k) are multiples of 3, where A001414 is the sum of prime factors with repetition and A276085 is the primorial base log-function.

Original entry on oeis.org

1, 8, 27, 35, 42, 64, 65, 77, 78, 95, 114, 119, 125, 143, 150, 155, 161, 180, 185, 186, 203, 209, 215, 216, 221, 222, 258, 275, 280, 287, 299, 305, 323, 329, 330, 335, 336, 341, 343, 365, 366, 371, 377, 395, 396, 402, 407, 413, 425, 437, 438, 473, 474, 485, 497, 510, 512, 515, 520, 527, 533, 545, 551, 575, 581, 582
Offset: 1

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Author

Antti Karttunen, Jun 02 2024

Keywords

Comments

As A001414 and A276085 are both fully additive, this sequence forms a multiplicative semigroup: if m and n are in the sequence, then so is m*n.

Crossrefs

Cf. A001414, A276085, A373372 (characteristic function).
Intersection of A289142 and A339746.
Positions of multiples of 3 in A373362.
Cf. also A373144.

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