A344995 Numbers k such that A051709(k)/A173557(k) is a positive natural number and a divisor of k.

4, 6, 12, 28, 42, 312, 456, 496, 588, 828, 1080, 1216, 1242, 1377, 1560, 4560, 5964, 7320, 7480, 7584, 8128, 11400, 13728, 14784, 23760, 33462, 59400, 59520, 124020, 147840, 188600, 277648, 321000, 543552, 1288224, 1510272, 1596048, 1964544, 2038140, 3323736, 3611520, 3780672, 3909816, 6137440, 9034032, 10783890

Offset: 1

Author

Antti Karttunen, Jun 05 2021

Keywords

• nonn

Links

• Index entries for sequences where odd perfect numbers must occur, if they exist at all

Crossrefs

Cf. A051709, A173557.

Subsequence of A344994.

Cf. also A344755, A345002.

Programs

PARI

A051709(n) = ((sigma(n) + eulerphi(n)) - (2*n));
A173557(n) = factorback(apply(p -> p-1, factor(n)[, 1]));
isA344995(n) = { my(u=A051709(n),t=A173557(n),r=u/t); ((u>0)&&(1==denominator(r)&&!(n%r))); };