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 A126577 #10 Oct 10 2019 13:46:24
%S A126577 1,4,7,176,9,133542,103,91072,99527,131023748,7591,300996993816,88001,
%T A126577 1403843964196,44094737,10686452707072,825533,368070779365071896502,
%U A126577 2895701,8653175044141052500,81659533540907,3080940707518158404
%N A126577 a(n) = numerator of the sum of reciprocals of the terms in n-th row of triangle A077581.
%e A126577 Row 4 of triangle A077581 is (1,3,5,7).
%e A126577 So a(4) is the numerator of 1/1 +1/3 +1/5 + 1/7 = 176/105.
%t A126577 row[n_] := Take[Select[Range[n^2], GCD[ #, n] == 1 &], n]; Table[Numerator[Plus @@ (1/# &) /@ row[n]], {n, 23}] (* _Ray Chandler_, Dec 29 2006 *)
%Y A126577 Cf. A077581, A126578.
%K A126577 frac,nonn
%O A126577 1,2
%A A126577 _Leroy Quet_, Dec 28 2006
%E A126577 Extended by _Ray Chandler_, Dec 29 2006