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A361563
Wagstaff numbers that are of the form 4*k + 1.
1
5, 13, 17, 61, 101, 313, 701, 1709, 2617, 10501, 42737, 95369, 138937, 267017, 374321
OFFSET
1,1
COMMENTS
15135397 is also in the sequence, but may not be the next term.
FORMULA
Intersection of A000978 and A002144.
PROG
(Python)
from itertools import count, islice
from sympy import prime, isprime
def A361563_gen(): # generator of terms
return filter(lambda p: not p&2 and isprime(((1<<p)+1)//3), (prime(n) for n in count(2)))
A361563_list = list(islice(A361563_gen(), 7)) # Chai Wah Wu, Mar 21 2023
CROSSREFS
Cf. A000978 (Wagstaff numbers), A002144 (primes of form 4*k + 1), A112634, A361562.
Sequence in context: A276260 A350379 A145040 * A376396 A195549 A294132
KEYWORD
nonn,more
AUTHOR
Jorge Coveiro, Mar 15 2023
STATUS
approved