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A236959
Number of nonzero cubic residues modulo the n-th prime.
2
1, 2, 4, 2, 10, 4, 16, 6, 22, 28, 10, 12, 40, 14, 46, 52, 58, 20, 22, 72, 24, 26, 82, 88, 32, 100, 34, 106, 36, 112, 42, 130, 136, 46, 148, 50, 52, 54, 166, 172, 178, 60, 190, 64, 196, 66, 70, 74, 226, 76, 232, 238, 80
OFFSET
1,2
FORMULA
If prime(n)-1=3k then a(n)=k otherwise a(n)=prime(n)-1.
EXAMPLE
a(4)=2 for residues of x^3 (mod 7=prime(4)) are 1 and 6;
a(3)=4 for residues of x^3 (mod 5=prime(3)) are 1, 2, 3, 4.
CROSSREFS
Sequence in context: A086930 A235798 A099585 * A366032 A097577 A097692
KEYWORD
nonn
AUTHOR
Carmine Suriano, Apr 22 2014
STATUS
approved