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 A346682 #13 Jul 30 2021 10:20:18 %S A346682 1,0,6,45,461,5020,57812,691586,8512048,107095262,1371219004, %T A346682 17808830924,234048288772,3106795261083,41593689788637, %U A346682 560980967638479,7614970691479315,103957059568762775,1426355910771621805,19658792867492660060,272046427837226505466 %N A346682 a(n) = Sum_{k=0..n} (-1)^(n-k) * binomial(6*k,k) / (5*k + 1). %H A346682 Seiichi Manyama, <a href="/A346682/b346682.txt">Table of n, a(n) for n = 0..856</a> %F A346682 G.f. A(x) satisfies: A(x) = 1 / (1 + x) + x * (1 + x)^5 * A(x)^6. %F A346682 a(n) ~ 2^(6*n + 6) * 3^(6*n + 13/2) / (49781 * sqrt(Pi) * n^(3/2) * 5^(5*n + 3/2)). - _Vaclav Kotesovec_, Jul 30 2021 %t A346682 Table[Sum[(-1)^(n - k) Binomial[6 k, k]/(5 k + 1), {k, 0, n}], {n, 0, 20}] %t A346682 nmax = 20; A[_] = 0; Do[A[x_] = 1/(1 + x) + x (1 + x)^5 A[x]^6 + O[x]^(nmax + 1) // Normal, nmax + 1]; CoefficientList[A[x], x] %o A346682 (PARI) a(n) = sum(k=0, n, (-1)^(n-k)*binomial(6*k, k)/(5*k + 1)); \\ _Michel Marcus_, Jul 29 2021 %Y A346682 Cf. A002295, A032357, A188678, A346065, A346666. %Y A346682 Cf. A346680, A346681, A346683, A346684. %K A346682 nonn %O A346682 0,3 %A A346682 _Ilya Gutkovskiy_, Jul 29 2021