A344994 Numbers k such that A173557(k) divides nonzero A051709(k).

4, 6, 8, 12, 16, 24, 27, 28, 32, 42, 48, 54, 60, 64, 96, 108, 112, 120, 126, 128, 150, 168, 176, 192, 204, 216, 240, 243, 250, 256, 294, 312, 378, 384, 396, 432, 440, 448, 456, 460, 480, 486, 496, 500, 504, 512, 540, 588, 672, 700, 768, 774, 828, 840, 864, 888, 924, 960, 972, 1000, 1014, 1024, 1080, 1134, 1176, 1216

Offset: 1

Author

Antti Karttunen, Jun 05 2021

Keywords

• nonn

Crossrefs

Cf. A051709, A173557.

Cf. A344995, A345054 (subsequences).

Cf. also A344754, A345051.

Programs

PARI

A051709(n) = ((sigma(n) + eulerphi(n)) - (2*n));
A173557(n) = factorback(apply(p -> p-1, factor(n)[, 1]));
isA344994(n) = { my(u=A051709(n)); ((u>0)&&(0==(u%A173557(n)))); };