A336557 Numbers k such that A336456(n) = Product_{p^e|n} A336456(p^e). Here each p^e is the maximal power of prime p that divides k, and A336456(n) = A335915(sigma(sigma(n))).

1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 23, 24, 25, 26, 27, 28, 29, 31, 32, 36, 37, 38, 39, 41, 43, 44, 45, 47, 48, 49, 50, 51, 53, 54, 56, 59, 60, 61, 62, 63, 64, 67, 68, 71, 72, 73, 74, 75, 76, 78, 79, 80, 81, 83, 86, 87, 89, 92, 95, 96, 97, 99, 100, 101, 103, 104, 107, 108, 109, 111, 112

Offset

1,2

Comments

Numbers at which points A336456 appears to be multiplicative.

Links

Antti Karttunen, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A335915, A336456.

Cf. A336556 (characteristic function), A336558 (complement).

Union of A000961 and A336559.

Union of A336547 and A336560.

Sequence in context: A014089 A065039 A171397 * A335235 A023804 A342851

Adjacent sequences: A336554 A336555 A336556 * A336558 A336559 A336560

Keyword

nonn

Author

Antti Karttunen, Jul 25 2020

Status

approved