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A280583 a(n) = product of divisors of the number of divisors of n. 1
1, 2, 2, 3, 2, 8, 2, 8, 3, 8, 2, 36, 2, 8, 8, 5, 2, 36, 2, 36, 8, 8, 2, 64, 3, 8, 8, 36, 2, 64, 2, 36, 8, 8, 8, 27, 2, 8, 8, 64, 2, 64, 2, 36, 36, 8, 2, 100, 3, 36, 8, 36, 2, 64, 8, 64, 8, 8, 2, 1728, 2, 8, 36, 7, 8, 64, 2, 36, 8, 64, 2, 1728, 2, 8, 36, 36, 8 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

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

FORMULA

a(n) = A007955(A000005(n)).

a(p) = 2 for p = primes (A000040).

a(n) = 3 for squares of primes (A001248).

EXAMPLE

For n = 6; a(n) = product of divisors (tau(6)) = 1*2*4 = 8.

MATHEMATICA

Table[Times@@Divisors[DivisorSigma[0, n]], {n, 80}] (* Harvey P. Dale, Dec 04 2021 *)

PROG

(MAGMA) [&*[d: d in Divisors(#[d: d in Divisors(n)])]: n in [1..100]]

CROSSREFS

Cf. A000005, A000040, A001248, A007955, A010553, A062069.

Sequence in context: A225244 A345281 A338319 * A177047 A339665 A334490

Adjacent sequences:  A280580 A280581 A280582 * A280584 A280585 A280586

KEYWORD

nonn

AUTHOR

Jaroslav Krizek, Jan 07 2017

STATUS

approved

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Last modified May 24 19:38 EDT 2022. Contains 354043 sequences. (Running on oeis4.)