A099395 One if odd part of n is 3, zero otherwise.

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

Offset: 1

Author

Ralf Stephan, Oct 21 2004

Keywords

• nonn

Comments

Characteristic function of A007283.

Links

• Antti Karttunen, Table of n, a(n) for n = 1..65537
• Index entries for characteristic functions

Crossrefs

First differences of A099396.

Cf. A000265, A007283.

Programs

Mathematica

Differences[Join[{0,0},Floor[Log[2,2/3 Range[2,130]]]]] (* Harvey P. Dale, Mar 01 2012 *)

Scheme

(define (A099395 n) (if (= 3 (A000265 n)) 1 0)) ;; Antti Karttunen, Dec 06 2017

Formula

G.f.: Sum_{k>=0} x^(3*2^k).