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 A280785 #9 May 01 2020 07:56:38 %S A280785 1,1,1,2,2,1,5,5,2,1,13,13,6,2,1,35,35,16,6,2,1,95,95,46,17,6,2,1,262, %T A280785 262,128,49,17,6,2,1,727,727,364,139,50,17,6,2,1,2033,2033,1029,401, %U A280785 142,50,17,6,2,1,5714,5714,2930,1147,412,143,50,17,6,2,1,16136,16136,8344,3299,1184,415,143,50,17,6,2,1 %N A280785 Triangle read by rows: numbers of nonintersecting circles, one marked. %H A280785 R. J. Mathar, <a href="http://arxiv.org/abs/1603.00077">Topologically Distinct Sets of Non-intersecting Circles in the Plane</a>, arXiv:1603.00077 [math.CO], 2016. %e A280785 Triangle begins: %e A280785 1, %e A280785 1,1, %e A280785 2,2,1, %e A280785 5,5,2,1, %e A280785 13,13,6,2,1, %e A280785 35,35,16,6,2,1, %e A280785 95,95,46,17,6,2,1, %e A280785 262,262,128,49,17,6,2,1, %e A280785 727,727,364,139,50,17,6,2,1, %e A280785 ... %Y A280785 Row sums are A000107. %K A280785 nonn,tabl %O A280785 1,4 %A A280785 _N. J. A. Sloane_, Jan 20 2017