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 A288690 #5 Jun 14 2017 10:20:17
%S A288690 1,1,7,64,633,5801,48245,372345,2743793,19706380,139666975,983424751,
%T A288690 6902981425,48383824035,338898209049,2373012819041,16613639684833,
%U A288690 116304663546706,814166474511867,5699292259116239,39895529322328145,279270568611716769,1954901225698086549
%N A288690 Number of n-digit biquanimous strings using digits {0,1,...,6}.
%C A288690 A biquanimous string is a string whose digits can be split into two groups with equal sums.
%H A288690 Alois P. Heinz, <a href="/A288690/b288690.txt">Table of n, a(n) for n = 0..1000</a>
%H A288690 <a href="/index/Rec#order_17">Index entries for linear recurrences with constant coefficients</a>, signature (35, -557, 5373, -35284, 167758, -599018, 1643178, -3510009, 5878447, -7726457, 7932089, -6287970, 3771376, -1654048, 500240, -93216, 8064).
%F A288690 G.f.: -(4032*x^20 -50640*x^19 +300760*x^18 -1131816*x^17 +2828844*x^16 -5169218*x^15 +7372355*x^14 -8685305*x^13 +8984178*x^12 -8471674*x^11 +7172188*x^10 -5192457*x^9 +3073627*x^8 -1446472*x^7 +532167*x^6 -150791*x^5 +32203*x^4 -4997*x^3 +529*x^2 -34*x +1) / ((7*x-1) *(4*x-1) *(3*x-1)^2 *(2*x-1)^5 *(x-1)^8).
%Y A288690 Column k=6 of A288638.
%K A288690 nonn,easy
%O A288690 0,3
%A A288690 _Alois P. Heinz_, Jun 13 2017