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 A144631 #8 Sep 08 2022 08:45:38
%S A144631 4,12,880,46900,1615824,45094896,1115345088,25519125060,553014576400,
%T A144631 11514200107696,232490008680384,4581732884262352,88532684825838400,
%U A144631 1683073282734360000,31561148509363526400,584964180982546208100
%N A144631 Second diagonal (or column) of A144630.
%H A144631 Klaus Brockhaus, <a href="/A144631/b144631.txt">Table of n, a(n) for n=2..100</a>
%p A144631 invH := proc(n,i,j) (-1)^(i+j)*(i+j-1)*binomial(n+i-1,n-j)*binomial(n+j-1,n-i)* (binomial(i+j-2,i-1))^2 ; end: A144630 := proc(n,k) local T,i,j ; T := 0 ; for i from n-k+1 to n do for j from n-k+1 to n do T := T+invH(n,i,j) ; od; od; RETURN(T) ; end: A144631 := proc(n) A144630(n+1,2) ; end: for n from 1 to 20 do printf("%a,",A144631(n)) : od: # _R. J. Mathar_, Jan 21 2009
%o A144631 (Magma) [ [ &+[I[i][j]: i, j in [k..n] ]: k in [n..1 by -1] ][2] where I:=H^-1 where H:=Matrix(Rationals(), n, n, [ < i, j, 1/(i+j-1) >: i, j in [1..n] ] ): n in [2..17] ]; // _Klaus Brockhaus_, Jan 22 2009
%K A144631 nonn
%O A144631 2,1
%A A144631 Daniel McLaury and Ben Golub, Jan 20 2009
%E A144631 More terms from _R. J. Mathar_ and _Klaus Brockhaus_, Jan 21 2009