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A288102 Number of solutions to x^7 + y^7 = z^7 mod n. 9
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 (list; graph; refs; listen; history; text; internal format)
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: A211055 A136769 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

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Last modified December 16 05:59 EST 2018. Contains 318158 sequences. (Running on oeis4.)