A278579 Quadratic non-residues of 23: numbers n such that Jacobi(n,23) = -1.

5, 7, 10, 11, 14, 15, 17, 19, 20, 21, 22, 28, 30, 33, 34, 37, 38, 40, 42, 43, 44, 45, 51, 53, 56, 57, 60, 61, 63, 65, 66, 67, 68, 74, 76, 79, 80, 83, 84, 86, 88, 89, 90, 91, 97, 99, 102, 103, 106, 107, 109, 111, 112, 113, 114, 120, 122, 125, 126, 129, 130, 132, 134, 135, 136, 137, 143, 145, 148, 149

Offset

1,1

Comments

Important for the study of Ramanujan numbers A000594.

References

Wilton, John Raymond. "Congruence properties of Ramanujan's function τ(n)." Proceedings of the London Mathematical Society 2.1 (1930): 1-10. See page 1.

Links

Table of n, a(n) for n=1..70.

Index entries for linear recurrences with constant coefficients, signature (1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, -1).

Formula

From Robert Israel, Nov 30 2016: (Start)

a(n+11) = a(n)+23.

G.f.: (x^11+x^10+x^9+x^8+2*x^7+2*x^6+x^5+3*x^4+x^3+3*x^2+2*x+5)/(x^12-x^11-x+1). (End)

Mathematica

LinearRecurrence[{1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, -1}, {5, 7, 10, 11, 14, 15, 17, 19, 20, 21, 22, 28}, 80] (* Harvey P. Dale, Jan 12 2020 *)

Crossrefs

Cf. A028736, A000594, A063987, A278580.

For the primes in this sequence see A191065.

Sequence in context: A056818 A028736 A028759 * A088707 A241265 A189290

Adjacent sequences: A278576 A278577 A278578 * A278580 A278581 A278582

Keyword

nonn

Author

N. J. A. Sloane, Nov 29 2016

Status

approved