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 A081370 #16 Aug 26 2025 17:43:18
%S A081370 1,30,105,120,132,231,252,380,495,520,595,616,630,680,756,858,870,924,
%T A081370 1040,1155,1173,1365,1428,1463,1547,1610,1722,1768,1820,1953,1976,
%U A081370 1995,2002,2016,2080,2093,2170,2184,2277,2310,2508,2520,2530,2552,2618,2622
%N A081370 Numbers k such that binomial(k^2, k) reduced mod k^2 is 0.
%H A081370 Amiram Eldar, <a href="/A081370/b081370.txt">Table of n, a(n) for n = 1..10000</a>
%H A081370 Max Alekseyev, <a href="https://oeis.org/wiki/User:Max_Alekseyev/gpscripts#Binomial_coefficients_modulo_integers">PARI/GP Scripts for Miscellaneous Math Problems: Binomial coefficients modulo integers</a> (binomod.gp).
%t A081370 Do[s=Mod[Binomial[n^2, n], n^2]; If[s==0, Print[n]], {n, 1, 10000}]
%t A081370 Select[Range[3000],Mod[Binomial[#^2,#],#^2]==0&] (* _Harvey P. Dale_, Aug 26 2025 *)
%o A081370 (PARI) is(k) = binomod(k^2, k, k^2) == 0; \\ _Amiram Eldar_, Jul 30 2024, using _Max Alekseyev_'s binomod.gp
%Y A081370 Cf. A014062, A081369.
%K A081370 nonn,changed
%O A081370 1,2
%A A081370 _Labos Elemer_, Mar 20 2003