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 A377187 #13 Nov 12 2024 20:38:20
%S A377187 3,11,2,9,19,5,27,14,29,3,19,13,5,41,7,51,26,53,27,55,4,33,67,17,69,
%T A377187 35,71,9,83,14,85,43,29,44,89,5,51,103,13,21,53,107,27,109,11,123,62,
%U A377187 125,63,127,64,129,65,131,6,73,49,37,149,25,151,19,17,77,155,13
%N A377187 Triangle read by rows: T(n,k) = numerator((n^2 + k)/(n^2 - k)).
%D A377187 Steven R. Finch, Mathematical Constants, Encyclopedia of Mathematics and its Applications, vol. 94, Cambridge University Press, Section 1.3, p. 14.
%F A377187 Limit_{n->oo} Product_{k=1..n} T(n,k)/A377188(n,k) = e = A001113 (see Finch).
%F A377187 T(n,n) = A026741(n+1).
%F A377187 T(n,2) = A164900(n-1).
%e A377187 The triangle begins as:
%e A377187 3;
%e A377187 11, 2;
%e A377187 9, 19, 5;
%e A377187 27, 14, 29, 3;
%e A377187 19, 13, 5, 41, 7;
%e A377187 51, 26, 53, 27, 55, 4;
%e A377187 33, 67, 17, 69, 35, 71, 9;
%e A377187 83, 14, 85, 43, 29, 44, 89, 5;
%e A377187 51, 103, 13, 21, 53, 107, 27, 109, 11;
%e A377187 ...
%t A377187 T[n_,k_]:=Numerator[(n^2+k)/(n^2-k)]; Table[T[n,k],{n,2,12},{k,2,n}]//Flatten
%o A377187 (Python)
%o A377187 from math import isqrt, comb, gcd
%o A377187 def A377187(n): return (d:=(a:=(m:=isqrt(k:=n-1<<1))+(k>m*(m+1))+1)**2+(b:=n-comb(a-1,2)))//gcd(d,d-(b<<1)) # _Chai Wah Wu_, Nov 12 2024
%Y A377187 Cf. A001113, A026741, A063656, A164900, A377188 (denominator).
%K A377187 nonn,easy,frac,tabl
%O A377187 2,1
%A A377187 _Stefano Spezia_, Oct 19 2024