OFFSET
1,3
MATHEMATICA
Union[PowerMod[Range[56], 2, 56]] (* Alonso del Arte, Dec 28 2019 *)
PROG
(Sage) [quadratic_residues(56)] # Zerinvary Lajos, May 24 2009
(Scala) (1 to 56).map(n => (n * n) % 56).toSet.toSeq.sorted // Alonso del Arte, Dec 28 2019
CROSSREFS
KEYWORD
nonn,fini,full,easy
AUTHOR
STATUS
approved