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

1,1

Links

Table of n, a(n) for n=1..66.

Prog

(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)))); };

Crossrefs

Cf. A051709, A173557.

Cf. A344995, A345054 (subsequences).

Cf. also A344754, A345051.

Sequence in context: A020225 A310663 A162294 * A211026 A090989 A161219

Adjacent sequences: A344991 A344992 A344993 * A344995 A344996 A344997

Keyword

nonn

Author

Antti Karttunen, Jun 05 2021

Status

approved