



0, 0, 0, 0, 0, 0, 2, 0, 4, 0, 0, 0, 0, 4, 0, 0, 0, 8, 0, 0, 6, 0, 0, 0, 0, 0, 12, 8, 0, 0, 0, 0, 0, 0, 10, 16, 0, 0, 0, 0, 0, 12, 0, 0, 20, 0, 0, 0, 14, 0, 0, 0, 0, 24, 0, 16, 0, 0, 0, 0, 0, 0, 38, 0, 0, 0, 0, 0, 0, 20, 0, 32, 0, 0, 0, 0, 22, 0, 0, 0, 36, 0, 0
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OFFSET

1,7


COMMENTS

Number of integers d from 0 to n1 such that x^3 + y^3 == d (mod n) has no solutions in integers.


LINKS

Table of n, a(n) for n=1..83.


PROG

(Python) [nlen(set((pow(x, 3, n)+pow(y, 3, n))%n for x in range(n) for y in range(x+1))) for n in range(1, 51)]
(PARI) a(n) = my(v=[]); for (x=1, n, for (y=1, n, v = concat(v, Mod(x, n)^3 + Mod(y, n)^3))); n  #Set(v); \\ Michel Marcus, Jul 10 2018


CROSSREFS

Cf. A305211.
Sequence in context: A261162 A218862 A243199 * A104774 A087263 A099894
Adjacent sequences: A305209 A305210 A305211 * A305213 A305214 A305215


KEYWORD

nonn,changed


AUTHOR

Jack Zhang, May 27 2018


EXTENSIONS

a(50)a(83) from Jon E. Schoenfield, May 28 2018


STATUS

approved



