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 A049623 #9 Dec 16 2019 22:10:10
%S A049623 2,3,7,12,17,22,31,38,45,56,65,74,91,100,111,130,141,154,177,190,205,
%T A049623 230,249,264,291,312,329,360,379,396,433,452,481,518,539,570,611,636,
%U A049623 659,704,731,756,809,834,861,914,947,978,1031,1066,1099,1154,1199,1232,1291,1336,1371,1436,1469,1502,1575
%N A049623 a(n) = T(n,n+3), array T as in A049615.
%H A049623 G. C. Greubel, <a href="/A049623/b049623.txt">Table of n, a(n) for n = 0..1000</a>
%t A049623 T[n_, k_]:= Length[Select[Flatten[Table[{x, y}, {x,0,n}, {y,0,k}], 1], GCD @@ # > 1 &]]; Table[T[n, n+3], {n,0,65}] (* _G. C. Greubel_, Dec 16 2019 *)
%Y A049623 Cf. A049615, A049616, A049617, A049618, A049619, A049620, A049621, A049622.
%K A049623 nonn
%O A049623 0,1
%A A049623 _Clark Kimberling_
%E A049623 Terms a(37) onward added by _G. C. Greubel_, Dec 16 2019