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A282925 Expansion of Product_{k>=1} (1 - x^(7*k))^28/(1 - x^k)^29 in powers of x. 2

%I #32 Sep 08 2022 08:46:18

%S 1,29,464,5365,49880,394632,2750969,17296732,99742368,534126988,

%T 2681856693,12722233068,57373155952,247218913828,1022189562610,

%U 4070289420139,15656921120982,58336024110584,211023516790156,742643172981206,2547265600634862,8529351700138885

%N Expansion of Product_{k>=1} (1 - x^(7*k))^28/(1 - x^k)^29 in powers of x.

%H Seiichi Manyama, <a href="/A282925/b282925.txt">Table of n, a(n) for n = 0..1000</a>

%F G.f.: Product_{n>=1} (1 - x^(7*n))^28/(1 - x^n)^29.

%F a(n) ~ exp(Pi*sqrt(350*n/21)) * sqrt(175) / (4*sqrt(3) * 7^(29/2) * n). - _Vaclav Kotesovec_, Nov 10 2017

%t nmax = 30; CoefficientList[Series[Product[(1 - x^(7*k))^28/(1 - x^k)^29, {k, 1, nmax}], {x, 0, nmax}], x] (* _Vaclav Kotesovec_, Nov 10 2017 *)

%o (PARI) my(N=30,x='x+O('x^N)); Vec(prod(j=1, N, (1 - x^(7*j))^28/(1 - x^j)^29)) \\ _G. C. Greubel_, Nov 18 2018

%o (Magma) m:=30; R<x>:=PowerSeriesRing(Integers(), m); Coefficients(R!( (&*[(1 - x^(7*j))^28/(1 - x^j)^29: j in [1..m+2]]) )); // _G. C. Greubel_, Nov 18 2018

%o (Sage)

%o R = PowerSeriesRing(ZZ, 'x')

%o prec = 30

%o x = R.gen().O(prec)

%o s = prod((1 - x^(7*j))^28/(1 - x^j)^29 for j in (1..prec))

%o print(s.coefficients()) # _G. C. Greubel_, Nov 18 2018

%Y Cf. A282919.

%K nonn

%O 0,2

%A _Seiichi Manyama_, Feb 24 2017

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Last modified April 23 07:42 EDT 2024. Contains 371905 sequences. (Running on oeis4.)