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 A103366 #13 Jul 11 2025 11:22:27 %S A103366 1,-3,12,-70,585,-6741,103068,-2023092,49615695,-1487006785, %T A103366 53477384268,-2272859942574,112699083156751,-6447858833644515, %U A103366 421601806346674320,-31242589674606301224,2604618355967848204587,-242686626407684239621113,25124942798118355122058980 %N A103366 Second column of triangle A103364, which equals the matrix inverse of the Narayana triangle (A001263). %H A103366 Vaclav Kotesovec, <a href="/A103366/b103366.txt">Table of n, a(n) for n = 2..200</a> %F A103366 a(n) ~ (-1)^n * 2^(2*n-5) * n! * (n-1)! / (BesselJ(2, BesselJZero(1, 1)) * BesselJZero(1, 1)^(2*n-4)), where BesselJZero(1, 1) = A115369. - _Vaclav Kotesovec_, Jul 11 2025 %o A103366 (PARI) a(n)=if(n<2,0,(matrix(n,n,m,j,binomial(m-1,j-1)*binomial(m,j-1)/j)^-1)[n,2]) %Y A103366 Cf. A001263, A103364, A103365, A103367, A115369. %K A103366 sign %O A103366 2,2 %A A103366 _Paul D. Hanna_, Feb 02 2005