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

 

Logo

The October issue of the Notices of the Amer. Math. Soc. has an article about the OEIS.

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A175169 Numbers n such that n divides the sum of digits of 2^n. 9
1, 2, 5, 70 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

No other terms <= 200000. - Harvey P. Dale, Dec 16 2010

No other terms <= 1320000. - Robert G. Wilson v, Dec 18 2010

There are almost certainly no further terms.

LINKS

Table of n, a(n) for n=1..4.

MATHEMATICA

Select[Range[200000], Divisible[Total[IntegerDigits[2^#]], #]&]

(* Harvey P. Dale, Dec 16 2010 *)

PROG

(PARI) is(n)=sumdigits(2^n)%n==0 \\ Charles R Greathouse IV, Sep 06 2016

CROSSREFS

Sum of digits of k^n mod n: (k=2) A000079, A001370, A175434, A175169; (k=3) A000244, A004166, A175435, A067862; (k=5) A000351, A066001, A175456; (k=6) A000400, A066002, A175457, A067864; (k=7) A000420, A066003, A175512, A067863; (k=8) A062933; (k=13) A001022, A175527, A175528, A175525; (k=21) A175589; (k=167) A175558, A175559, A175560, A175552.

Sequence in context: A268211 A246280 A133004 * A066933 A132496 A100009

Adjacent sequences:  A175166 A175167 A175168 * A175170 A175171 A175172

KEYWORD

nonn,base

AUTHOR

N. J. A. Sloane, Dec 03 2010

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 September 25 22:57 EDT 2018. Contains 315425 sequences. (Running on oeis4.)