A317924 Integers m, not powers of primes (A000961), such that A071324(m) = A206369(m).

20, 28, 44, 52, 68, 76, 92, 99, 100, 116, 117, 124, 148, 153, 164, 171, 172, 188, 196, 207, 212, 236, 244, 261, 268, 272, 279, 284, 292, 304, 316, 332, 333, 356, 368, 369, 387, 388, 404, 412, 423, 428, 436, 452, 464, 477, 484, 496, 500, 508, 524, 531, 548, 549, 556, 592, 596

Offset

1,1

Comments

For powers of primes x, we have A071324(x) = A206369(x), so this sequence lists the integers m that have the same property even though they are not powers of primes.

Links

Amiram Eldar, Table of n, a(n) for n = 1..10000

Prog

(PARI) a071324(n) = my(d=Vecrev(divisors(n))); sum(k=1, #d, (-1)^(k+1)*d[k]);
a206369(n) = sumdiv(n, d, eulerphi(n/d) * issquare(d));
isok(n) = (n!=1) && !isprimepower(n) && (a071324(n) == a206369(n));

Crossrefs

Cf. A000961, A071324, A206369.

Intersection of A024619 and A317923.

Sequence in context: A124318 A309780 A139703 * A355445 A145567 A344795

Adjacent sequences: A317921 A317922 A317923 * A317925 A317926 A317927

Keyword

nonn

Author

Michel Marcus, Aug 11 2018

Status

approved