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 A057762 #18 Apr 02 2025 21:49:49
%S A057762 1,2,4,5,10,11,19,20,22,29,31,38,41,44,55,58,59,61,62,71,76,79,82,89,
%T A057762 95,101,109,110,116,118,121,122,124,131,139,142,145,149,151,155,158,
%U A057762 164,178,179,181,190,191,199,202,205,209,211,218,220,229
%N A057762 Numbers k such that 5 is a square mod k.
%C A057762 Numbers not divisible by 3, 8, or 25 and whose prime factors > 5 are congruent to +/- 1 mod 5. - _Eric M. Schmidt_, Jan 24 2014
%H A057762 T. D. Noe, <a href="/A057762/b057762.txt">Table of n, a(n) for n=1..1000</a>
%p A057762 with(numtheory); [seq(mroot(5,2,p),p=1..400)];
%t A057762 Prepend[ Select[ Range[300], Reduce[ Mod[5 - k^2, #] == 0, k, Integers] =!= False &], 1] (* _Jean-François Alcover_, Sep 20 2012 *)
%t A057762 Join[{1, 2, 4, 5}, Select[Range[6, 300], MemberQ[Mod[Range[#]^2, #], 5] &]] (* _T. D. Noe_, Sep 20 2012 *)
%Y A057762 Cf. A057126, A057125, A057763.
%K A057762 nonn
%O A057762 1,2
%A A057762 _N. J. A. Sloane_, Nov 01 2000