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A336559 Numbers k, not powers of primes, such that A336456(k) = Product_{p^e|k} A336456(p^e). Here each p^e is the maximal power of prime p that divides k, and A336456(k) = A335915(sigma(sigma(k))). 6
6, 12, 14, 15, 18, 20, 24, 26, 28, 36, 38, 39, 44, 45, 48, 50, 51, 54, 56, 60, 62, 63, 68, 72, 74, 75, 76, 78, 80, 86, 87, 92, 95, 96, 99, 100, 104, 108, 111, 112, 116, 117, 122, 123, 124, 126, 134, 143, 144, 146, 147, 148, 150, 153, 158, 159, 162, 171, 172, 175, 176, 180, 183, 188, 192, 194, 196, 200, 204, 206, 207 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
PROG
(PARI) isA336559(n) = ((n>1) && !isprimepower(n) && A336556(n)); \\ Needs also code from A336556.
CROSSREFS
Terms of A336557 without those of A000961.
Cf. A336549 (a subsequence).
Sequence in context: A004758 A055051 A338054 * A348551 A143957 A318981
KEYWORD
nonn
AUTHOR
Antti Karttunen, Jul 25 2020
STATUS
approved

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Last modified June 30 07:39 EDT 2024. Contains 373861 sequences. (Running on oeis4.)