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A317924
Integers m, not powers of primes (A000961), such that A071324(m) = A206369(m).
2
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
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
Intersection of A024619 and A317923.
Sequence in context: A124318 A309780 A139703 * A355445 A145567 A344795
KEYWORD
nonn
AUTHOR
Michel Marcus, Aug 11 2018
STATUS
approved