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 A331756 #9 Sep 14 2022 10:41:14
%S A331756 0,2,8,23,52,107,190,324,514,781,1128,1604,2192,2962,3896,5026,6372,
%T A331756 8030,9940,12243,14874,17899,21324,25324,29772,34850,40496,46827,
%U A331756 53798,61687,70244,79852,90348,101842,114312,127946,142576,158700,176048,194788,214812
%N A331756 a(n) = A306302(n)/2.
%t A331756 z[n_] := Sum[If[GCD[i, j] == 1, (n-i+1)(n-j+1), 0], {i, n}, {j, n}];
%t A331756 a[n_] := If[n == 0, 0, (z[n] + n^2 + 2n)/2];
%t A331756 Table[a[n], {n, 0, 33}] (* _Jean-François Alcover_, Sep 14 2022 *)
%Y A331756 Cf. A306302.
%K A331756 nonn
%O A331756 0,2
%A A331756 _N. J. A. Sloane_, Feb 04 2020