login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A102390 An odious count. 3

%I #14 Aug 05 2023 13:16:18

%S 0,1,2,0,3,0,0,4,5,0,0,6,0,7,8,0,9,0,0,10,0,11,12,0,0,13,14,0,15,0,0,

%T 16,17,0,0,18,0,19,20,0,0,21,22,0,23,0,0,24,0,25,26,0,27,0,0,28,29,0,

%U 0,30,0,31,32,0,33,0,0,34,0,35,36,0,0,37,38,0,39,0,0,40,0,41,42,0,43,0,0,44

%N An odious count.

%C Counting numbers appear at positions indexed by the odious numbers A000069, 0 otherwise.

%C Equals row sums of triangle A143466 starting with offset 1. - _Gary W. Adamson_, Aug 17 2008

%H Amiram Eldar, <a href="/A102390/b102390.txt">Table of n, a(n) for n = 0..10000</a>

%F a(n) = (1+floor(n/2))*(1-(-1)^A000120(n))/2.

%F a(n) = (1+floor(n/2))*(1-(-1)^A010060(n))/2.

%F A008619(n) = A102389(n) + a(n).

%t a[n_] := (1 + Floor[n/2])*(1 - (-1)^DigitCount[n, 2, 1])/2; Array[a, 100, 0] (* _Amiram Eldar_, Jul 22 2023 *)

%Y Cf. A000120, A008619, A010060, A102389, A143466.

%K easy,nonn,base

%O 0,3

%A _Paul Barry_, Jan 06 2005

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified August 27 15:26 EDT 2024. Contains 375470 sequences. (Running on oeis4.)