A288102 Number of solutions to x^7 + y^7 = z^7 mod n.

1, 4, 9, 20, 25, 36, 49, 112, 99, 100, 121, 180, 169, 196, 225, 704, 289, 396, 361, 500, 441, 484, 529, 1008, 725, 676, 1377, 980, 589, 900, 961, 4864, 1089, 1156, 1225, 1980, 1369, 1444, 1521, 2800, 1681, 1764, 4999, 2420, 2475, 2116, 2209, 6336, 10633, 2900

Offset

1,2

Comments

Equivalently, the number of solutions to x^7 + y^7 + z^7 == 0 (mod n). - Andrew Howroyd, Jul 17 2018

Links

Seiichi Manyama, Table of n, a(n) for n = 1..1000

Prog

(PARI) a(n)={my(p=Mod(sum(i=0, n-1, x^lift(Mod(i, n)^7)), 1-x^n)); polcoeff(lift(p^3), 0)} \\ Andrew Howroyd, Jul 17 2018

Crossrefs

Number of solutions to x^k + y^k = z^k mod n: A062775 (k=2), A063454 (k=3), A288099 (k=4), A288100 (k=5), A288101 (k=6), this sequence (k=7), A288103 (k=8), A288104 (k=9), A288105 (k=10).

Sequence in context: A136769 A351600 A115075 * A288100 A063454 A288104

Adjacent sequences: A288099 A288100 A288101 * A288103 A288104 A288105

Keyword

nonn,mult

Author

Seiichi Manyama, Jun 05 2017

Extensions

Keyword:mult added by Andrew Howroyd, Jul 17 2018

Status

approved