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%I #12 May 09 2020 15:05:54
%S 1,17,49,59,979,91,167,731,5111,517,1817,6071,109,18241,22289,2771,
%T 131,28823,67,51619,11911,34891,15557,257,1949,22313,2267,14123,
%U 153931,5273999,1,3167,45091,3569,268309,126947,4217,127,369641,201679,85739
%N Numerator of Sum_{k=1..n} k^4 / Product_{k=1..n} k^4.
%C a(n) = 1 for n = {1, 31, 59, 94, 104, 122, 133, 181, 206, 223, ...} = A166604.
%e The first few fractions are 1, 17/16, 49/648, 59/55296, 979/207360000, 91/10749542400, 167/23044331520000, ... = A181426/A334734.
%t Table[Numerator[Sum[ k^4, {k, 1, n}] / Product[k^4, {k, 1, n}]], {n, 1, 100}]
%o (PARI) a(n) = numerator(sum(k=1, n, k^4)/prod(k=1, n, k^4)); \\ _Michel Marcus_, May 09 2020
%Y Cf. A090585 = Numerator of Sum/Product of first n numbers.
%Y Cf. A125294 = Numerator of Sum/Product of squares of first n numbers.
%Y Cf. A166604, A334734 (denominators).
%K nonn,frac
%O 1,2
%A _Alexander Adamchuk_, Oct 18 2010
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