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 A321197 #7 Nov 14 2018 01:12:25
%S A321197 1,0,-1,1,-1,3,-4,10,-20,42,-98,210,-492,1122,-2607,6149,-14443,34463,
%T A321197 -82238,197574,-476918,1154402,-2807516,6845016,-16743674,41067512,
%U A321197 -100967539,248843095,-614546545,1520779665
%N A321197 a(n) gives the A-sequence for the Riordan matrix (1/(1 + x^2 - x^3), x/(1 + x^2 - x^3)) from A321196.
%C A321197 See the recurrence formula for A321196 from the A- and Z-sequences.
%F A321197 a(n) = [t^n] (1/f(t)), where f(t) = F^{[-1]}(t)/t, with the compositional inverse F^{[-1]}(t) of F(x) = 1/(1 + x^2 - x^3). The expansion of f is given by (-1)^n*A001005(n), for n >= 0.
%Y A321197 Cf. A001005, A321196.
%K A321197 sign
%O A321197 0,6
%A A321197 _Wolfdieter Lang_, Oct 30 2018