A283991 a(1) = 0 and for n > 1, a(n) = 1 if Stern polynomial B(n,x) is irreducible, 0 otherwise.

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

Offset

1

Comments

Characteristic function for A186891 (apart from term 1, which is here defined as a(1) = 0).

Links

Antti Karttunen, Table of n, a(n) for n = 1..65537

Prog

(PARI)
\\ After Charles R Greathouse IV's code for A186891.
ps(n) = if(n<2, n, if(n%2, ps(n\2)+ps(n\2+1), 'x*ps(n\2)));
A283991(n) = polisirreducible(ps(n));

Crossrefs

Cf. A186891, A125184, A260443.

Cf. A283992 (partial sums).

Differs from A010051 for the first time at n=25: here a(25) = 1.

Differs from A257000 for the first time at n=65: here a(65) = 1.

Sequence in context: A010051 A358751 A252233 * A353499 A359372 A327861

Adjacent sequences: A283988 A283989 A283990 * A283992 A283993 A283994

Keyword

nonn

Author

Antti Karttunen, Mar 20 2017

Status

approved