OFFSET
1,1
COMMENTS
k is an omnipower of odd prime p if k is an n-th power (mod p) for all 1 <= n < (p-1)/2.
Nonzero omnipowers of p form a subgroup of the multiplicative group mod p.
Primes of form 2p^k+1, p prime, k >= 0. That is, primes p such that (p-1)/2 is a prime power (A000961).
LINKS
Jianing Song, Table of n, a(n) for n = 1..10000
PROG
(PARI) isA048184(n) = (n==3) || (isprime(n) && (n>2) && isprimepower((n-1)/2))
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
STATUS
approved