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A037046
Numbers that are not the number of quadratic residues mod n for any n.
3
5, 13, 17, 25, 26, 29, 35, 39, 41, 43, 47, 50, 58, 59, 61, 65, 67, 71, 73, 78, 83, 85, 86, 89, 94, 95, 101, 103, 107, 109, 113, 116, 118, 119, 122, 123, 125, 127, 130, 131, 134, 143, 145, 146, 149, 155, 163, 167, 170, 173, 178, 179, 181, 183, 185, 188, 191, 193
OFFSET
1,1
COMMENTS
Complement of A037041. - Michel Marcus, Nov 11 2015
MATHEMATICA
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 *)
CROSSREFS
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).
Sequence in context: A087895 A092101 A105596 * A126887 A339952 A087445
KEYWORD
nonn
STATUS
approved