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 A112477 #13 May 26 2024 05:31:01
%S A112477 1,1,1,-2,-1,1,6,2,-3,1,-22,-6,10,-5,1,90,22,-38,22,-7,1,-394,-90,158,
%T A112477 -98,38,-9,1,1806,394,-698,450,-194,58,-11,1,-8558,-1806,3218,-2126,
%U A112477 978,-334,82,-13,1,41586,8558,-15310,10286,-4942,1838,-526,110,-15,1,-206098,-41586,74614,-50746,25150,-9922,3142,-778,142,-17,1
%N A112477 Riordan array ((1-x+sqrt(1+6*x+x^2))/2, (sqrt(1+6*x+x^2)-x-1)/2).
%e A112477 Triangle starts:
%e A112477 1;
%e A112477 1, 1;
%e A112477 -2, -1, 1;
%e A112477 6, 2, -3, 1;
%e A112477 -22, -6, 10, -5, 1;
%e A112477 90, 22, -38, 22, -7, 1;
%e A112477 ...
%t A112477 T[n_,k_]:=SeriesCoefficient[(1-x+Sqrt[1+6x+x^2])((Sqrt[1+6x+x^2]-x-1)/2)^k/2,{x,0,n}]; Table[T[n,k],{n,0,9},{k,0,n}]//Flatten (* _Stefano Spezia_, May 26 2024 *)
%Y A112477 Inverse of triangle A112475. Row sums are A112478.
%K A112477 easy,sign,tabl
%O A112477 0,4
%A A112477 _Paul Barry_, Sep 07 2005