This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A160461 #16 Aug 11 2025 06:26:41
%S A160461 1,2,5,10,20,35,63,105,175,280,444,685,1050,1575,2345,3439,5005,7195,
%T A160461 10275,14525,20405,28428,39375,54150,74080,100715,136265,183365,
%U A160461 245645,327485,434810,574790,756965,992950,1297940,1690500,2194642,2839695,3663225,4711160
%N A160461 Coefficients in the expansion of C/B^2, in Watson's notation of page 106.
%H A160461 Seiichi Manyama, <a href="/A160461/b160461.txt">Table of n, a(n) for n = 0..1000</a>
%H A160461 Watson, G. N., <a href="https://gdz.sub.uni-goettingen.de/id/PPN243919689_0179">Ramanujans Vermutung ueber Zerfaellungsanzahlen.</a> J. Reine Angew. Math. (Crelle), 179 (1938), 97-128.
%F A160461 See Maple code in A160458 for formula.
%F A160461 a(n) ~ sqrt(3)*exp(sqrt(6*n/5)*Pi)/(20*n). - _Vaclav Kotesovec_, Nov 26 2016
%F A160461 G.f.: 1/Product_{n > = 1} ( 1 - x^(n/gcd(n,k)) ) for k = 5. Cf. A000041 (k = 1), A015128 (k = 2), A278690 (k = 3) and A298311 (k = 4). - Peter Bala, Nov 17 2020
%e A160461 x^3+2*x^27+5*x^51+10*x^75+20*x^99+35*x^123+63*x^147+...
%t A160461 nmax = 50; CoefficientList[Series[Product[(1 - x^(5*k))/(1 - x^k)^2, {k, 1, nmax}], {x, 0, nmax}], x] (* _Vaclav Kotesovec_, Nov 26 2016 *)
%Y A160461 Cf. Product_{n>=1} (1 - x^(5*n))^k/(1 - x^n)^(k + 1): this sequence (k=1), A160462 (k=2), A160463 (k=3), A160506 (k=4), A071734 (k=5), A160460 (k=6), A160521 (k=7), A278555 (k=12), A278556 (k=18), A278557 (k=24), A278558 (k=30).
%Y A160461 Cf. A000041, A015128, A278690, A298311.
%K A160461 nonn,easy
%O A160461 0,2
%A A160461 _N. J. A. Sloane_, Nov 13 2009