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 A110129 #32 Feb 16 2025 08:32:58 %S A110129 1,2,22,504,16966,752800,41492284,2734083968,209681631814, %T A110129 18348172005888,1804161160185748,196945525458761728, %U A110129 23633625832975567644,3092337510752711057408,438161926888980929318584,66838962347916069718425600,10921339483491720513675526726,1903085098399657078831752282112 %N A110129 Central coefficients of a scaled Legendre triangle. %C A110129 Central coefficients of triangle A110124. %H A110129 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/LegendrePolynomial.html">Legendre Polynomial</a>. %H A110129 Wikipedia, <a href="https://en.wikipedia.org/wiki/Legendre_polynomials">Legendre polynomials</a>. %F A110129 a(n) = 2^n*LegendreP(n, n). %F A110129 a(n) = Sum_{j=0..floor(n/2)} (-1)^j*C(n, j)*C(2*n-2*j, n)*n^(n-2*j). %F A110129 a(n) ~ 2^(2*n) * n^(n - 1/2) / sqrt(Pi). - _Vaclav Kotesovec_, Nov 07 2021 %p A110129 a:= n-> LegendreP(n$2)*2^n: %p A110129 seq(a(n), n=0..17); # _Alois P. Heinz_, Nov 17 2024 %t A110129 Table[2^n LegendreP[n,n],{n,0,20}] (* _Harvey P. Dale_, Nov 28 2012 *) %o A110129 (PARI) a(n)=pollegendre(n,n)<<n \\ _Charles R Greathouse IV_, Mar 19 2017 %Y A110129 Cf. A008556, A110124, A349077, A349113, A349114, A349115. %K A110129 easy,nonn %O A110129 0,2 %A A110129 _Paul Barry_, Jul 13 2005