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 A322760 #11 Mar 16 2025 09:27:14 %S A322760 1,1,3,25,343,1701,117406179,1377144939510210299,7319582701014978251, %T A322760 68957488738377254912,31655878065328599351648522128233122128960851, %U A322760 509835253962108047546712884688217781173085736103608399459708858847501357,254487582354743232569912323057838854214490688232159609663484703619 %N A322760 Denominator of Product_{i=1..n, j=1..n, k=1..n, m=1..n} (i+j+k+m-2)/(i+j+k+m-3). %C A322760 The sequence of rationals A322759/A322760 is the natural successor to A000984 and A008793. %D A322760 Miklos Bona, editor, Handbook of Enumerative Combinatorics, CRC Press, 2015, page 576, line 3, with a=b=c=d=n. %e A322760 1, 2, 500/3, 406594944/25, 17946021496671970416/343, 266763232240477060473636852903291418/1701, ... %p A322760 f4:=proc(n) local a,i,j,k,m; %p A322760 a:=1; %p A322760 for i from 1 to n do %p A322760 for j from 1 to n do %p A322760 for k from 1 to n do %p A322760 for m from 1 to n do %p A322760 a:=a*(i+j+k+m-2)/(i+j+k+m-3); od: od: od: od: a; end; %p A322760 t1 := [seq(f4(n),n=0..12)]; %o A322760 (PARI) a(n) = denominator(prod(i=1,n,prod(j=1,n,prod(k=1,n,prod(m=1,n,(i+j+k+m-2)/(i+j+k+m-3)))))) \\ _Georg Fischer_, Mar 16 2025 %Y A322760 Cf. A000984, A008793, A322759. %K A322760 nonn,frac %O A322760 0,3 %A A322760 _N. J. A. Sloane_, Dec 28 2018 %E A322760 1 prepended by _Georg Fischer_, Mar 16 2025