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A288105 Number of solutions to x^10 + y^10 = z^10 mod n. 9
1, 4, 9, 24, 25, 36, 49, 192, 99, 100, 201, 216, 169, 196, 225, 1024, 289, 396, 361, 600, 441, 804, 529, 1728, 3125, 676, 1377, 1176, 841, 900, 601, 6144, 1809, 1156, 1225, 2376, 1369, 1444, 1521, 4800, 1201, 1764, 1849, 4824, 2475, 2116, 2209, 9216, 2695, 12500 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Chai Wah Wu, Table of n, a(n) for n = 1..10000 (terms 1..1000 from Seiichi Manyama)

MATHEMATICA

Table[cnt=0; Do[If[Mod[x^10 + y^10 - z^10, n]==0, cnt++], {x, 0, n-1}, {y, 0, n-1}, {z, 0, n-1}]; cnt, {n, 50}] (* Vincenzo Librandi, Jul 18 2018 *)

PROG

(Python)

def A288105(n):

    ndict = {}

    for i in range(n):

        m = pow(i, 10, n)

        if m in ndict:

            ndict[m] += 1

        else:

            ndict[m] = 1

    count = 0

    for i in ndict:

        ni = ndict[i]

        for j in ndict:

            k = (i+j) % n

            if k in ndict:

                count += ni*ndict[j]*ndict[k]

    return count # Chai Wah Wu, Jun 05 2017

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), A288103 (k=8), A288104 (k=9), this sequence (k=10).

Sequence in context: A272252 A067801 A062775 * A288101 A320913 A320059

Adjacent sequences:  A288102 A288103 A288104 * A288106 A288107 A288108

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 10 05:49 EST 2018. Contains 318044 sequences. (Running on oeis4.)