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A375166
Nonsquares congruent to {0, 1, 4, 7} modulo 9.
0
7, 10, 13, 18, 19, 22, 27, 28, 31, 34, 37, 40, 43, 45, 46, 52, 54, 55, 58, 61, 63, 67, 70, 72, 73, 76, 79, 82, 85, 88, 90, 91, 94, 97, 99, 103, 106, 108, 109, 112, 115, 117, 118, 124, 126, 127, 130, 133, 135, 136, 139, 142, 145, 148, 151, 153, 154, 157, 160, 162
OFFSET
1,1
COMMENTS
Squares are congruent to {0, 1, 4, 7} modulo 9, but the reverse is not always true since there are nonsquares that have the same congruence property. See Beiler.
REFERENCES
Albert H. Beiler, Recreations in the theory of numbers, New York, Dover, (2nd ed.) 1966. See p. 140.
MATHEMATICA
Select[Range[0, 162], !IntegerQ[Sqrt[#]] && MemberQ[{0, 1, 4, 7}, Mod[#, 9]] &]
CROSSREFS
Intersection of A000037 and A056991.
Sequence in context: A327137 A026319 A120153 * A226969 A007770 A212979
KEYWORD
nonn,easy
AUTHOR
Stefano Spezia, Aug 05 2024
STATUS
approved