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 A050148 #14 Jul 31 2025 11:54:29
%S A050148 1,7,32,160,832,4424,23872,130176,715520,3957448,21998176,122786976,
%T A050148 687736896,3863423880,21758302848,122811081216,694533774336,
%U A050148 3934558067336,22323615621280,126832567223712,721500116473664
%N A050148 a(n) = T(n,n-2), array T as in A050143.
%C A050148 Also T(2*n-2,n-2), array T as in A055807.
%F A050148 a(n) = Sum_{s=1..n} binomial(n,s)*binomial(s+n-4,n-3) = n*hypergeom([-n + 1, n-2], [2], -1) for n >= 3. - _Petros Hadjicostas_, Feb 13 2021
%F A050148 D-finite with recurrence (n-1)*(n-3)*a(n) +(-8*n^2+41*n-48)*a(n-1) +(13*n^2-95*n+162)*a(n-2) -2*(n-2)*(n-6)*a(n-3)=0 for n-3>=3. - _R. J. Mathar_, Jul 31 2025
%Y A050148 Cf. A050143, A055807.
%K A050148 nonn
%O A050148 2,2
%A A050148 _Clark Kimberling_