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A158520 Numbers n such that 2^n divided by the number of digits of 2^n is an integer. 1
0, 1, 2, 3, 4, 5, 6, 10, 11, 12, 13, 24, 25, 26, 50, 51, 52, 53, 103, 104, 105, 106, 210, 211, 212, 422, 423, 424, 425, 848, 849, 850, 1698, 1699, 1700, 3399, 3400, 3401, 6800, 6801, 6802, 6803, 13604, 13605, 13606, 27210, 27211, 27212, 27213 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Also n such that A000079(n)/A034887(n) is an integer.

LINKS

Table of n, a(n) for n=1..49.

MATHEMATICA

ndnQ[n_]:=Module[{n2=2^n}, Divisible[n2, IntegerLength[n2]]]; Select[Range[ 0, 28000], ndnQ] (* Harvey P. Dale, Apr 16 2013 *)

CROSSREFS

Cf. A000079, A034887

Sequence in context: A032970 A137691 A215726 * A032868 A032341 A023761

Adjacent sequences:  A158517 A158518 A158519 * A158521 A158522 A158523

KEYWORD

nonn,base,easy

AUTHOR

Ctibor O. Zizka, Mar 20 2009

EXTENSIONS

Extended by R. J. Mathar, Mar 26 2009

STATUS

approved

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Last modified April 20 16:17 EDT 2019. Contains 322310 sequences. (Running on oeis4.)