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 A171695 #6 Mar 31 2022 13:40:39
%S A171695 1,1,1,-1,6,-1,-1,7,25,-7,10,-44,152,-20,-2,-26,198,-292,1628,-642,94,
%T A171695 -154,1000,-1954,6416,1586,-1400,266,1646,-13606,51774,-75094,175226,
%U A171695 -73890,15962,-1378,1000,-3936,-4448,190432,37104,779104,-472160,133152,-15128
%N A171695 Expansion of g.f.: 2^(floor((n+1)/2))*n!*(1-y)^(n+1)*f(x, y, m), where f(x, y, m) = 2^(m+1)*exp(2^m*t)/((1-y*exp(t))*(1 + (2^(m+1)-1)*exp(2^m*t))), and m = 1.
%H A171695 G. C. Greubel, <a href="/A171695/b171695.txt">Rows n = 0..40 of the triangle, flattened</a>
%F A171695 G.f.: 2^(floor((n+1)/2))*n!*(1-y)^(n+1)*f(x, y, m), where f(x, y, m) = 2^(m+1)*exp(2^m*t)/((1-y*exp(t))*(1 + (2^(m+1)-1)*exp(2^m*t))), and m = 1.
%e A171695 Triangle begins as:
%e A171695 1;
%e A171695 1, 1;
%e A171695 -1, 6, -1;
%e A171695 -1, 7, 25, -7;
%e A171695 10, -44, 152, -20, -2;
%e A171695 -26, 198, -292, 1628, -642, 94;
%e A171695 -154, 1000, -1954, 6416, 1586, -1400, 266;
%e A171695 1646, -13606, 51774, -75094, 175226, -73890, 15962, -1378;
%e A171695 1000, -3936, -4448, 190432, 37104, 779104, -472160, 133152, -15128;
%t A171695 m= 1;
%t A171695 f[t_, y_, m_]= 2^(m+1)*Exp[2^m*t]/((1-y*Exp[t])*(1+(2^(m+1)-1)*Exp[2^m*t]));
%t A171695 Table[CoefficientList[2^(Floor[(n+1)/2])*n!*(1-y)^(n+1)*SeriesCoefficient[ Series[f[t,y,m], {t,0,20}], n], y], {n,0,12}]//Flatten (* modified by _G. C. Greubel_, Mar 29 2022 *)
%Y A171695 Cf. A060187, A159041, A171692, A171693, A171694.
%K A171695 sign,tabl
%O A171695 0,5
%A A171695 _Roger L. Bagula_, Dec 15 2009
%E A171695 Edited by _G. C. Greubel_, Mar 29 2022