A138328 Number of ways in which n can be represented as p+g, where p is a prime and g is a primitive root of p.

0, 0, 1, 0, 1, 0, 1, 1, 0, 1, 0, 1, 1, 0, 1, 0, 1, 1, 2, 2, 1, 2, 1, 2, 0, 0, 1, 2, 2, 1, 2, 2, 2, 3, 0, 0, 2, 1, 2, 2, 0, 3, 3, 3, 0, 1, 2, 4, 0, 2, 0, 4, 2, 2, 5, 4, 2, 3, 1, 2, 4, 2, 3, 0, 3, 1, 5, 1, 6, 3, 4, 4, 4, 2, 2, 3, 3, 5, 3, 3, 0, 4, 1, 3, 5, 4, 5, 4, 2, 2, 4, 6, 3, 1, 2, 4, 2, 4, 4, 0, 5, 6, 5, 7, 2

Offset

1,19

Links

T. D. Noe, Table of n, a(n) for n=1..10000

Crossrefs

Cf. A060749 (primitive roots), A138325 (least p such that n=p+g).

Sequence in context: A046816 A352248 A301475 * A137264 A289014 A193238

Adjacent sequences: A138325 A138326 A138327 * A138329 A138330 A138331

Keyword

nonn

Author

T. D. Noe, Mar 14 2008

Status

approved