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A226746 Numbers n such that x^2 = 1 has more than two solutions in the Gaussian integers modulo n. 2
4, 5, 6, 8, 10, 12, 13, 14, 15, 16, 17, 18, 20, 21, 22, 24, 25, 26, 28, 29, 30, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 44, 45, 46, 48, 50, 51, 52, 53, 54, 55, 56, 57, 58, 60, 61, 62, 63, 64, 65, 66, 68, 69, 70, 72, 73, 74, 75, 76, 77, 78, 80, 82, 84, 85 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
EXAMPLE
13 is in the sequence because 5i, 8i, 1 and 12 are solutions of x^2 = 1 (mod 13).
MATHEMATICA
h[n_] := Flatten[Table[a + b I, {a, 0, n - 1}, {b, 0, n - 1}]]; sol[n_] := Select[h[n], Mod[#^2, n] == 1 &]; Select[Range[100], Length[sol[#]] > 2 &]
CROSSREFS
Sequence in context: A328983 A223133 A295485 * A206416 A144043 A139446
KEYWORD
nonn
AUTHOR
STATUS
approved

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Last modified May 26 18:06 EDT 2024. Contains 372840 sequences. (Running on oeis4.)