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 A084543 #16 Jun 28 2024 05:22:41
%S A084543 3,-9,69,-531,6147,-73665,1143045,-18456795,359420355,-7279744185,
%T A084543 170639259525,-4151789871075,113815089771075,-3231091019581425,
%U A084543 101428235414230725,-3289812808335928875,116369085609950047875,-4244245621899589931625,167038144384492533277125
%N A084543 a(2,n) as defined in A003148.
%F A084543 D-finite with recurrence a(n) + 3*a(n-1) - 2*(2*n+3)*(n-1)*a(n-2) = 0. - _R. J. Mathar_, Mar 12 2013
%p A084543 A003148 := proc(m::integer,n::integer) doublefactorial(2*n+2*m+1)/(2*m+1)*simplify(hypergeom([ -n,m+1/2],[m+3/2],2)) ; end proc:
%p A084543 A084543 := proc(n::integer) A003148(2,n) ; end proc:
%p A084543 seq(A084543(n),n=0..40) : # _R. J. Mathar_, Apr 25 2006
%t A084543 a[m_, n_] := (2n + 2m + 1)!!/(2m + 1)*Hypergeometric2F1[-n, m + 1/2, m + 3/2, 2];
%t A084543 Table[a[2, n], {n, 0, 20}] (* _Jean-François Alcover_, Jul 31 2023, after _R. J. Mathar_ *)
%K A084543 sign,easy
%O A084543 0,1
%A A084543 _R. J. Mathar_, Jul 01 2003
%E A084543 More terms from _R. J. Mathar_, Apr 25 2006