OFFSET
1,1
MATHEMATICA
aa[n_] := Mod[Sum[PowerMod[ a + b I, n, n], {a, n}, {b, n}], n]; Select[Range[100], aa[72*#] > 0 &]
CROSSREFS
KEYWORD
nonn
AUTHOR
José María Grau Ribas, Oct 16 2013
EXTENSIONS
Terms a(7) onward from Max Alekseyev, Oct 16 2013
STATUS
approved