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 A055589 #16 Sep 21 2024 11:13:17 %S A055589 0,1,6,26,96,321,1002,2972,8472,23392,62912,165504,427264,1085184, %T A055589 2717184,6718464,16427008,39763968,95387648,226951168,535953408, %U A055589 1257046016,2929852416,6789267456,15648423936,35888562176,81927340032 %N A055589 Convolution of A049612 with A011782. %C A055589 Sixth column of triangle A055587. T(n,4) of array T as in A049600. %H A055589 <a href="/index/Rec#order_05">Index entries for linear recurrences with constant coefficients</a>, signature (10, -40, 80, -80, 32). %F A055589 a(n)= T(n, 4)= A055587(n+4, 5). %F A055589 G.f.: x*((1-x)^4)/(1-2*x)^5. %Y A055589 Cf. A049600, A049612, A055587, A011782. %K A055589 nonn,easy %O A055589 0,3 %A A055589 _Wolfdieter Lang_ May 30 2000