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 A295289 #4 Nov 19 2017 19:08:39
%S A295289 1,-1,0,3,-8,9,19,-141,448,-759,-951,14355,-71810,238617,-421622,
%T A295289 -1283181,17699702,-110524503,494858579,-1480719213,12947578,
%U A295289 41684591673,-396443074054,2562153015315,-12548536326806,39305562343881,52542301031459,-2158744047173613
%N A295289 Expansion of 1/(1 + x + x^2/(1 + 2*x + x^2/(1 + 3*x + x^2/(1 + 4*x + x^2/(1 + ...))))), a continued fraction.
%t A295289 nmax = 27; CoefficientList[Series[1/(1 + x + ContinuedFractionK[x^2, 1 + (k + 1) x, {k, 1, nmax}]), {x, 0, nmax}], x]
%Y A295289 Cf. A000110, A001464, A006789.
%K A295289 sign
%O A295289 0,4
%A A295289 _Ilya Gutkovskiy_, Nov 19 2017