A304109 a(n) = 1 if binary expansion of n encodes a squarefree (0,1)-polynomial when the factorization is done in polynomial ring GF(2)[X], 0 otherwise.

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

Offset

1

Links

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

Index entries for characteristic functions

Index entries for sequences related to polynomials in ring GF(2)[X]

Formula

a(n) = abs(A091219(n)).

Prog

(PARI) A304109(n) = { my(fm=factor(Pol(binary(n))*Mod(1, 2))); for(k=1, #fm~, if(fm[k, 2] > 1, return(0))); (1); };

Crossrefs

Absolute values of A091219.

Characteristic function of A304107.

Cf. also A304108, A304110 (partial sums), A304111.

Sequence in context: A359579 A246142 A091219 * A275601 A281011 A016416

Adjacent sequences: A304106 A304107 A304108 * A304110 A304111 A304112

Keyword

nonn

Author

Antti Karttunen, May 13 2018

Status

approved