# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a037046 Showing 1-1 of 1 %I A037046 #16 Nov 11 2015 08:51:01 %S A037046 5,13,17,25,26,29,35,39,41,43,47,50,58,59,61,65,67,71,73,78,83,85,86, %T A037046 89,94,95,101,103,107,109,113,116,118,119,122,123,125,127,130,131,134, %U A037046 143,145,146,149,155,163,167,170,173,178,179,181,183,185,188,191,193 %N A037046 Numbers that are not the number of quadratic residues mod n for any n. %C A037046 Complement of A037041. - _Michel Marcus_, Nov 11 2015 %t A037046 s = Length[Union@ #] & /@ Table[Mod[k^2, n], {n, 10000}, {k, 0, n - 1}]; Complement[Range@ Max@ #, #] &@ Take[Union@ s, 136] (* _Michael De Vlieger_, Nov 10 2015 *) %Y A037046 Cf. A000224, A096008, A111986 (number of numbers having n quadratic residues), A111987 (least number having n quadratic residues), A111988 (greatest number having n quadratic residues). %K A037046 nonn %O A037046 1,1 %A A037046 _David W. Wilson_ # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE