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A305816
a(n) = 1 if n is a prime whose binary expansion encodes a (0,1)-polynomial which is irreducible when factored over GF(2), 0 otherwise.
4
0, 1, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0
OFFSET
1
COMMENTS
Characteristic function of A091206.
FORMULA
a(n) = A010051(n)*A091225(n).
a(n) = [A305789(n) == 2].
PROG
(PARI) A305816(n) = (isprime(n)&&polisirreducible(Pol(binary(n))*Mod(1, 2)));
CROSSREFS
Cf. A091206, A305802, A305789, A305817 (partial sums), A305904.
Sequence in context: A284901 A071981 A280910 * A359820 A241979 A200244
KEYWORD
nonn
AUTHOR
Antti Karttunen, Jun 15 2018
STATUS
approved