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 A059030 #8 Oct 27 2023 22:00:46 %S A059030 4,6,2,10,12,4,16,18,6,22,24,8,28,30,10,34,36,12,40,42,14,46,48,16,52, %T A059030 54,18,58,60,20,64,66,22,70,72,24,76,78,26,82,84,28,88,90,30,94,96,32, %U A059030 100,102,34,106,108,36,112,114,38,118,120,40,124,126,42,130 %N A059030 Fourth main diagonal of A059026: a(n) = B(n+3,n) = lcm(n+3,n)/(n+3) + lcm(n+3,n)/n - 1 for all n >= 1. %F A059030 G.f.: x(2x^3+2x^2+6x+4)/(1-x^3)^2. %p A059030 B := (n,m) -> lcm(n,m)/n + lcm(n,m)/m - 1: seq(B(m+3,m),m=1..90); %Y A059030 Cf. A059026, A059029, A059031. %K A059030 nonn,easy %O A059030 1,1 %A A059030 _Asher Auel_, Dec 15 2000