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 A355574 #20 Feb 26 2025 08:54:33
%S A355574 2,90,223,2686,31601,370894,4220160,46962379,512600193
%N A355574 Number of nonnegative integers k with n digits such that x^2 - s*x + p has only integer roots, where s and p denote the sum and product of the digits of k respectively.
%C A355574 a(n) is the number of n-digit numbers in A355497.
%F A355574 a(n) <= A063945(n).
%F A355574 Limit_{n->oo} a(n)/a(n-1) = 10.
%Y A355574 Cf. A355497.
%Y A355574 Cf. A007953, A007954, A063945, A355547.
%K A355574 nonn,base,hard,more
%O A355574 1,1
%A A355574 _Stefano Spezia_, Jul 07 2022
%E A355574 a(8)-a(9) from _Jean-Marc Rebert_, Jul 13 2022