login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A163297 a(n) = sum of divisors of n plus length of the binary expansion of n. 1
1, 4, 6, 9, 9, 15, 11, 18, 17, 22, 16, 32, 18, 28, 28, 35, 23, 44, 25, 47, 37, 41, 29, 65, 36, 47, 45, 61, 35, 77, 37, 68, 54, 60, 54, 97, 44, 66, 62, 96, 48, 102, 50, 90, 84, 78, 54, 130, 63, 99, 78, 104, 60, 126, 78, 126, 86, 96, 66, 174, 68, 102, 110, 133, 91, 151, 75, 133 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

The length of the binary expansion of n is ceiling(log_2(n)).

LINKS

G. C. Greubel, Table of n, a(n) for n = 1..1000

FORMULA

a(n) = A000203(n) + A029837(n). - Michel Marcus, Jul 14 2015

MAPLE

A029837 := proc(n) ceil(log[2](n)) ; end: A163297 := proc(n) numtheory[sigma](n)+A029837(n) ; end: seq(A163297(n), n=1..100) ; # R. J. Mathar, Jul 26 2009

MATHEMATICA

Table[DivisorSigma[1, n]+Ceiling[Log[2, n]], {n, 70}] (* Harvey P. Dale, Nov 21 2014 *)

PROG

(PARI) vector(60, n, sigma(n)+ceil(log(n)/log(2))) \\ Michel Marcus, Jul 14 2015

(MAGMA) [SumOfDivisors(n)+Ceiling(Log(n)/Log(2)) : n in [1..70]]; // Vincenzo Librandi, Jul 14 2015

CROSSREFS

Cf. A000203, A029837.

Sequence in context: A341577 A094115 A339856 * A051679 A010378 A166593

Adjacent sequences:  A163294 A163295 A163296 * A163298 A163299 A163300

KEYWORD

nonn,base,less

AUTHOR

Juri-Stepan Gerasimov, Jul 25 2009

EXTENSIONS

A 37 changed to 36 by R. J. Mathar, Jul 26 2009

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
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified July 29 23:30 EDT 2021. Contains 346346 sequences. (Running on oeis4.)