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 A049628 #15 Jun 26 2022 17:31:02
%S A049628 1,4,8,14,22,34,48,68,92,122,156,200,248,308,374,448,530,628,732,854,
%T A049628 984,1126,1278,1452,1634,1836,2050,2282,2526,2798,3078,3388,3714,4060,
%U A049628 4422,4808,5206,5640,6092,6568,7060,7592,8136,8722,9328,9958,10610,11308
%N A049628 a(n) = Sum_{i=0..n} T(i,n-i) where T is A049627.
%o A049628 (PARI) T(n,k) = (n+1)*(k+1) - sum(i=0, n, sum(j=0, k, gcd(i,j)>1)); \\ A049627
%o A049628 a(n) = sum(i=0, n, T(i,n-i)); \\ _Michel Marcus_, Aug 06 2021
%Y A049628 Cf. A049627.
%Y A049628 Partial sums of A225531.
%K A049628 nonn
%O A049628 0,2
%A A049628 _Clark Kimberling_
%E A049628 More terms from _Sean A. Irvine_, Aug 05 2021