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 A349975 #14 Dec 13 2021 02:45:56 %S A349975 0,0,0,0,3,8,17,31,51,77,112,155,208,272,348,436,539,656,789,939,1107, %T A349975 1293,1500,1727,1976,2248,2544,2864,3211,3584,3985,4415,4875,5365, %U A349975 5888,6443,7032,7656,8316,9012,9747,10520,11333,12187,13083,14021,15004,16031,17104 %N A349975 Expansion of g.f. (x^4*(x^2 + 2*x + 3))/((x - 1)^4*(x + 1)*(x^2 + x + 1)). %C A349975 Number of subsets of [n] having a distset (set of distances, see definition in A349976) of cardinality 4. %H A349975 <a href="/index/Rec#order_07">Index entries for linear recurrences with constant coefficients</a>, signature (2,0,-1,-1,0,2,-1). %Y A349975 Column k=4 of A349976. %K A349975 nonn,easy %O A349975 0,5 %A A349975 _Peter Luschny_, Dec 10 2021