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A244670 Product of divisors of n / sum of divisors of n for n such that product of divisors of n is divisible by sum of divisors of n. 2
1, 3, 392, 11250, 131769, 1568294784, 501126, 119439360000000, 6566468639062500, 39226324511250000, 15780962, 162778775259375000, 2966827112704, 22417760034702144000000000000, 1801703513076518898, 30261936128, 3531477204506250000, 5876813016539072244 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..18.

FORMULA

a(n) = A007955(A145551(n)) / A000203(A145551(n)) = A244668(A145551(n)).

EXAMPLE

For n = 4; A145551(4) = 30; A244668(30) = 11250.

PROG

(MAGMA)[Numerator((&*[d: d in Divisors(n)]) / (&+[d: d in Divisors(n)])): n in [1..10000] | Denominator((&*[d: d in Divisors(n)]) / (&+[d: d in Divisors(n)])) eq 1]

CROSSREFS

Cf. A007955, A000203, A145551, A244668, A244669.

Sequence in context: A193154 A120061 A187942 * A199146 A137023 A203563

Adjacent sequences:  A244667 A244668 A244669 * A244671 A244672 A244673

KEYWORD

nonn

AUTHOR

Jaroslav Krizek, Jul 04 2014

STATUS

approved

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Last modified December 5 00:21 EST 2021. Contains 349530 sequences. (Running on oeis4.)