login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A092668 Bisection of A000011. 1
1, 2, 4, 9, 23, 63, 190, 612, 2056, 7155, 25482, 92205, 337594, 1246863, 4636390, 17334801, 65108062, 245492244, 928772650, 3524337980, 13409202676, 51141124287, 195470831356, 748607855769, 2872202028517, 11038251159312 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..25.

MAPLE

with(numtheory): b:= proc(n) local s, d; if n = 0 then RETURN(1) else s := 2^(floor(n/2)); for d in divisors(n) do s := s+(phi(2*d)*2^(n/d))/(2*n); od; RETURN(s/2); fi; end: seq(b(2*n-1), n=1..30); - Emeric Deutsch, Feb 13 2006

CROSSREFS

Cf. A000011, A000117.

Sequence in context: A001573 A135307 A000083 * A164039 A014137 A245158

Adjacent sequences:  A092665 A092666 A092667 * A092669 A092670 A092671

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane, Nov 24 2004

EXTENSIONS

More terms from Emeric Deutsch, Feb 13 2006

STATUS

approved

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified October 20 20:02 EDT 2018. Contains 316402 sequences. (Running on oeis4.)