A373478 Numbers k such that A001414(k) and A003415(k) are both multiples of 3, where A001414 is the sum of prime factors with repetition, and A003415 is the arithmetic derivative.

1, 8, 9, 14, 20, 26, 27, 35, 38, 44, 50, 62, 64, 65, 68, 72, 74, 77, 81, 86, 92, 95, 110, 112, 116, 119, 122, 125, 126, 134, 143, 146, 155, 158, 160, 161, 164, 170, 180, 185, 188, 194, 196, 203, 206, 208, 209, 212, 215, 216, 218, 221, 230, 234, 236, 242, 243, 254, 275, 278, 280, 284, 287, 290, 299, 302, 304, 305

Offset

1,2

Comments

A multiplicative semigroup; if m and n are in the sequence then so is m*n.

Links

Antti Karttunen, Table of n, a(n) for n = 1..20000

Prog

(PARI) isA373478 = A373477;

Crossrefs

Cf. A001414, A003415, A373477 (characteristic function).

Positions of multiples of 3 in A373364.

Intersection of A289142 and A327863.

Disjoint union of A373475 and A373479.

Sequence in context: A059869 A327863 A213016 * A105833 A323249 A257037

Adjacent sequences: A373475 A373476 A373477 * A373479 A373480 A373481

Keyword

nonn

Author

Antti Karttunen, Jun 07 2024

Status

approved