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A056679
Primes p such that 1 + x + Sum_{q prime <= p} x^q is irreducible over GF(2).
0
2, 5, 17, 59, 73, 269, 3769, 4327
OFFSET
1,1
EXAMPLE
a(3) = 17 because 1 + x + x^2 + x^3 + x^5 + x^7 + x^11 + x^13 + x^17 is irreducible over GF(2).
PROG
(PARI) lista(nn) = {my(f=1+x); forprime(p=2, nn, f+=x^p; if(polisirreducible(Mod(1, 2)*f), print1(p, ", "))); } \\ Jinyuan Wang, Apr 15 2020
CROSSREFS
Cf. A071642.
Sequence in context: A134128 A119254 A278394 * A084528 A149993 A148413
KEYWORD
nonn,more
AUTHOR
Robert G. Wilson v, Nov 10 2000
EXTENSIONS
a(7)-a(8) from Jinyuan Wang, Apr 15 2020
STATUS
approved