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A370830
Primes p such that the polynomial x^4-x^3-x^2-x-1 is irreducible mod p.
2
2, 5, 31, 43, 53, 79, 83, 89, 97, 109, 131, 139, 151, 199, 229, 233, 239, 283, 313, 317, 359, 367, 389, 433, 443, 479, 487, 569, 571, 577, 601, 617, 641, 643, 659, 677, 769, 797, 823, 853, 857, 929, 937, 941, 971, 1013, 1019, 1049, 1063, 1069, 1087, 1093, 1117, 1163, 1171, 1181, 1231, 1249, 1283
OFFSET
1,1
LINKS
MAPLE
P:= x^4 - x^3 - x^2 - x - 1:
select(p -> Irreduc(P) mod p, [seq(ithprime(i), i=1..1000)]);
PROG
(Python)
from itertools import islice
from sympy import Poly, nextprime
from sympy.abc import x
def A370830_gen(): # generator of terms
p = 2
while True:
if Poly(x*(x*(x*(x-1)-1)-1)-1, x, modulus=p).is_irreducible:
yield p
p = nextprime(p)
A370830_list = list(islice(A370830_gen(), 20)) # Chai Wah Wu, Mar 14 2024
CROSSREFS
Subsequence of A106283. Cf. 106309.
Sequence in context: A059086 A363243 A215168 * A266478 A107389 A261750
KEYWORD
nonn
AUTHOR
Robert Israel, Mar 13 2024
STATUS
approved