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A344994
Numbers k such that A173557(k) divides nonzero A051709(k).
3
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
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. A344995, A345054 (subsequences).
Cf. also A344754, A345051.
Sequence in context: A020225 A310663 A162294 * A211026 A090989 A161219
KEYWORD
nonn
AUTHOR
Antti Karttunen, Jun 05 2021
STATUS
approved