A056679 Primes p such that 1 + x + Sum_{q prime <= p} x^q is irreducible over GF(2).
2, 5, 17, 59, 73, 269, 3769, 4327
Offset: 1
Examples
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).
Crossrefs
Cf. A071642.
Programs
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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
Extensions
a(7)-a(8) from Jinyuan Wang, Apr 15 2020