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A128398 Numbers n such that n^2 divides 18^n-1. 17
1, 17, 128583032925805678351 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

17 divides a(n) for n>1.

LINKS

Table of n, a(n) for n=1..3.

MATHEMATICA

a={}; Do[r=(18^n-1)/n^2; If[r==IntegerPart[r], AppendTo[a, n]], {n, 1, 10^3}]; a (* Vladimir Joseph Stephan Orlovsky, Aug 07 2008 *)

CROSSREFS

Subsequence of A128358.

Cf. A127103, A127104, A127105, A127106, A127107, A127102, A127101, A127100, A127092, A128405, A128393, A128394, A128395, A128396, A128397, A128398, A128399, A128400, A128401, A128402, A128403, A128404.

Sequence in context: A114432 A134686 A257305 * A257377 A246649 A210709

Adjacent sequences:  A128395 A128396 A128397 * A128399 A128400 A128401

KEYWORD

bref,hard,more,nonn

AUTHOR

Alexander Adamchuk, Mar 08 2007

STATUS

approved

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Last modified July 18 15:44 EDT 2019. Contains 325144 sequences. (Running on oeis4.)