A374118 Numbers k such that A328768(k) and A328845(k) are both multiples of 3, where A328768 is the first primorial based variant and A328845 is the first Fibonacci-based variant of the arithmetic derivative, respectively.

0, 1, 8, 9, 18, 27, 36, 45, 54, 63, 64, 65, 72, 81, 85, 90, 91, 95, 99, 108, 115, 117, 119, 125, 126, 133, 135, 143, 144, 153, 161, 162, 171, 175, 180, 185, 187, 189, 198, 205, 207, 209, 215, 216, 225, 234, 235, 243, 245, 252, 253, 259, 261, 270, 275, 279, 287, 288, 297, 301, 305, 306, 315, 324, 329, 333, 335, 342, 343

Offset

1,3

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..12000

Prog

(PARI) isA374118 = A374117;

Crossrefs

Cf. A328768, A328845, A374117 (characteristic function).

Indices of multiples of 3 in A374116.

Intersection of A373992 and A374122.

Sequence in context: A159836 A230542 A069809 * A067544 A022313 A120311

Adjacent sequences: A374115 A374116 A374117 * A374119 A374120 A374121

Keyword

nonn

Author

Antti Karttunen, Jul 08 2024

Status

approved