A091225 Characteristic function of A014580: 1 if the n-th GF(2)[X] polynomial is irreducible, 0 otherwise.

0, 0, 1, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 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, 1, 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, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0

Offset: 0

Author

Antti Karttunen, Jan 03 2004

Keywords

• nonn

Links

• Antti Karttunen, Table of n, a(n) for n = 0..100000
• A. Karttunen, Scheme-program for computing this sequence
• Index entries for characteristic functions
• Index entries for sequences operating on GF(2)[X]-polynomials

Crossrefs

a(n) = A010051(A091203(n)) = A010051(A091205(n)). Partial sums give A091226. Cf. A091227. Complementary to A091247.

Programs

PARI

a(n) = polisirreducible(Pol(binary(n))*Mod(1, 2)); \\ Michel Marcus, Nov 11 2017

Extensions

Data section extended up to a(120) by Antti Karttunen, Jan 01 2023