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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 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.)