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 A134836 #11 May 21 2025 19:01:19 %S A134836 1,1,1,1,3,1,1,5,3,1,1,7,8,3,1,1,9,16,8,3,1,1,11,27,20,8,3,1,1,13,41, %T A134836 43,20,8,3,1,1,15,58,81,48,20,8,3,1,1,17,78,138,106,48,20,8,3,1,1,19, %U A134836 101,218,213,112,48,20,8,3,1 %N A134836 Antidiagonals of the array: A007318 * A002260(transposed). %C A134836 Antidiagonals tend to A001792 starting from the right: (1, 3, 8, 20, 48, 112, ...). %F A134836 Antidiagonals of the array: A007318 * A002260(transform), where A002260 = (1; 1,2; 1,2,3; ...). %e A134836 First few rows of the array: %e A134836 1, 1, 1, 1, 1, 1, ...; %e A134836 1, 3, 3, 3, 3, 3, ...; %e A134836 1, 5, 8, 8, 8, 8, ...; %e A134836 1, 7, 16, 20, 20, 20, ...; %e A134836 1, 9, 27, 43, 48, 48, ...; %e A134836 1, 11, 41, 81, 106, 112, ...; %e A134836 ... %e A134836 First few rows of the triangle: %e A134836 1; %e A134836 1, 1; %e A134836 1, 3, 1; %e A134836 1, 5, 3, 1; %e A134836 1, 7, 8, 3, 1; %e A134836 1, 9, 16, 8, 3, 1; %e A134836 1, 11, 27, 20, 8, 3, 1; %e A134836 1, 13, 41, 43, 20, 8, 3, 1; %e A134836 ... %p A134836 A002260 := proc(n,k) %p A134836 if n <= k then %p A134836 n+1; %p A134836 else %p A134836 0 ; %p A134836 end if; %p A134836 end proc: %p A134836 A007318 := proc(n,k) %p A134836 if k <= n then %p A134836 binomial(n,k) ; %p A134836 else %p A134836 0 %p A134836 end if; %p A134836 end proc: %p A134836 A134836 := proc(n,k) %p A134836 add( A007318(n,i)*A002260(i,k),i=0..k) ; %p A134836 end proc: %p A134836 seq(seq(A134836(d-k,k),k=0..d),d=0..12) ; # _R. J. Mathar_, Aug 17 2022 %Y A134836 Cf. A002260, A001792, A116445 (array transposed), A001629 (antidiagonal sums). %K A134836 nonn,tabl,easy %O A134836 1,5 %A A134836 _Gary W. Adamson_, Nov 12 2007 %E A134836 One term corrected by _R. J. Mathar_, Aug 17 2022