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 A103778 #10 Sep 08 2019 01:50:46
%S A103778 1,0,1,0,-1,1,0,1,-2,1,0,0,3,-3,1,0,-4,-2,6,-4,1,0,14,-7,-7,10,-5,1,0,
%T A103778 -30,36,-6,-16,15,-6,1,0,33,-96,63,3,-30,21,-7,1,0,55,154,-209,88,25,
%U A103778 -50,28,-8,1,0,-429,0,429,-374,99,66,-77,36,-9,1,0,1365,-1014
%N A103778 Inverse of trinomial triangle A071675.
%C A103778 Inverse of Riordan array (1, x(1+x+x^2)) (A071675).
%F A103778 Riordan array (1, y) where y satisfies y + y^2 + y^3 = x; y = -2^(2/3)*((3*sqrt(3)*sqrt(27*x^2 + 14*x + 3) - 27*x - 7)^(1/3) - (3*sqrt(3)*sqrt(27*x^2 + 14*x + 3) + 27*x + 7)^(1/3) + 2^(1/3))/6.
%e A103778 Rows start
%e A103778 {1},
%e A103778 {0,1},
%e A103778 {0,-1,1},
%e A103778 {0,1,-2,1},
%e A103778 {0,0,3,-3,1},
%e A103778 ...
%Y A103778 Cf. A071675.
%K A103778 easy,sign,tabl
%O A103778 0,9
%A A103778 _Paul Barry_, Feb 15 2005