A340375 a(n) = 1 if n is of the form 2^i - 2^j with i >= j, and 0 otherwise.

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

Offset

0

Links

Antti Karttunen, Table of n, a(n) for n = 0..65537

Index entries for sequences related to binary expansion of n

Index entries for characteristic functions

Formula

a(0) = 1; for n > 1, a(n) = A209229(1+A000265(n)).

Prog

(PARI)
A000265(n) = (n>>valuation(n, 2));
A209229(n) = (n && !bitand(n, n-1));
A340375(n) = if(!n, 1, A209229(1+A000265(n)));
(PARI) A340375(n) = if(n<5, 1, n>>=valuation(n, 2); n++; n>>valuation(n, 2)==1); \\ From standalone function "is" given in A023758

Crossrefs

Characteristic function of A023758.

Cf. A000265, A209229.

Sequence in context: A221641 A144473 A011750 * A010055 A324290 A325964

Adjacent sequences: A340372 A340373 A340374 * A340376 A340377 A340378

Keyword

nonn

Author

Antti Karttunen, Jan 06 2021

Status

approved