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 A229242 #14 Sep 19 2013 12:59:32 %S A229242 1,4,19,91,379,436,2089,7561,8644,10009,36001,47956,144019,150841, %T A229242 198379,229771,821089,1100899,3009259,3419716,3933001,4554019,5274724, %U A229242 14328091,25272721,54726841,57312379,60034339,68221876,74727379,77994811,90262009,104544004 %N A229242 Generalized Markoff numbers: union of numbers a, b, c, d, e satisfying the Markoff(5) equation a^2 + b^2 + c^2 + d^2 + e^2 = 5*a*b*c*d*e. %e A229242 a(1)=1 since (1, 1, 1, 1, 1) is a solution to a^2 + b^2 + c^2 + d^2 + e^2 = 5*a*b*c*d*e. a(2)=4 since (4, 1, 1, 1, 1) is a solution. a(3)=19 since (19,4,1,1,1) is a solution. a(n) is the n-th leading term (that is a's) among all the solutions with a >= b >= c >= d >= e. %K A229242 nonn %O A229242 1,2 %A A229242 _Shanzhen Gao_, Sep 17 2013