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 A138463 #5 Mar 25 2024 09:08:45 %S A138463 2,22,394,8558,206098,5293446,142078746,3937603038,111818026018, %T A138463 3236724317174,95149655201962 %N A138463 A bisection of A006318. %F A138463 a(n)=A006318(2n+1). %F A138463 D-finite with recurrence +(n+1)*(2*n+1)*a(n) +(-70*n^2+3*n+4)*a(n-1) +(70*n^2-207*n+149)*a(n-2) -(n-2)*(2*n-5)*a(n-3)=0. - _R. J. Mathar_, Mar 25 2024 %p A138463 A138463 := proc(n) %p A138463 A006318(2*n+1) ; %p A138463 end proc: %p A138463 seq(A138463(n),n=0..50) ; # _R. J. Mathar_, Mar 25 2024 %K A138463 nonn %O A138463 0,1 %A A138463 _N. J. A. Sloane_, May 08 2008