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A288103 Number of solutions to x^8 + y^8 = z^8 mod n. 9
1, 4, 9, 24, 33, 36, 49, 192, 99, 132, 121, 216, 97, 196, 297, 1536, 385, 396, 361, 792, 441, 484, 529, 1728, 925, 388, 1377, 1176, 1121, 1188, 961, 12288, 1089, 1540, 1617, 2376, 1441, 1444, 873, 6336, 641, 1764, 1849, 2904, 3267, 2116, 2209, 13824, 2695, 3700 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

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

MATHEMATICA

Table[cnt=0; Do[If[Mod[x^8 + y^8 - z^8, n]==0, cnt++], {x, 0, n-1}, {y, 0, n-1}, {z, 0, n-1}]; cnt, {n, 50}] (* Vincenzo Librandi, Jul 18 2018 *)

PROG

(PARI) a(n)={my(p=Mod(sum(i=0, n-1, x^lift(Mod(i, n)^8)), 1-x^n)); vecsum(Vec( serconvol(lift(p^2) + O(x^n), lift(p) + O(x^n))))} \\ 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), A288102 (k=7), this sequence (k=8), A288104 (k=9), A288105 (k=10).

Sequence in context: A270461 A046422 A288099 * A286729 A159068 A255876

Adjacent sequences:  A288100 A288101 A288102 * A288104 A288105 A288106

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 November 19 00:12 EST 2019. Contains 329310 sequences. (Running on oeis4.)