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%I #16 Jan 24 2014 19:36:55
%S 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 95,101,109,110,116,118,121,122,124,131,139,142,145,149,151,155,158,
%U 164,178,179,181,190,191,199,202,205,209,211,218,220,229
%N Numbers n such that 5 is a square mod n.
%C 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 T. D. Noe, <a href="/A057762/b057762.txt">Table of n, a(n) for n=1..1000</a>
%p with(numtheory); [seq(mroot(5,2,p),p=1..400)];
%t Prepend[ Select[ Range[300], Reduce[ Mod[5 - k^2, #] == 0, k, Integers] =!= False &], 1] (* _Jean-François Alcover_, Sep 20 2012 *)
%t Join[{1, 2, 4, 5}, Select[Range[6, 300], MemberQ[Mod[Range[#]^2, #], 5] &]] (* _T. D. Noe_, Sep 20 2012 *)
%Y Cf. A057126, A057125, A057763.
%K nonn
%O 1,2
%A _N. J. A. Sloane_, Nov 01 2000
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