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A048184
Primes with nontrivial omnipower group.
4
3, 5, 7, 11, 17, 19, 23, 47, 59, 83, 107, 163, 167, 179, 227, 251, 257, 263, 347, 359, 383, 467, 479, 487, 503, 563, 587, 719, 839, 863, 887, 983, 1019, 1187, 1283, 1307, 1319, 1367, 1439, 1459, 1487, 1523, 1619, 1823, 1907, 2027, 2039, 2063, 2099, 2207
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
FORMULA
a(n) = 2*A364926(n) + 1. - Amiram Eldar, Mar 18 2026
MATHEMATICA
q[k_] := k > 2 && PrimeQ[k] && ((k-1)/2 == 1 || PrimePowerQ[(k-1)/2]); Select[Range[2300], q] (* Amiram Eldar, Mar 18 2026 *)
PROG
(PARI) isA048184(n) = (n==3) || (isprime(n) && (n>2) && isprimepower((n-1)/2))
CROSSREFS
Supersequence of A005385.
Sequence in context: A139559 A158361 A342692 * A290283 A163420 A155489
KEYWORD
nonn,easy
STATUS
approved