A138262 - OEIS

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A138262

Smallest positive integer m such that n divides [9^m/m] (=A129799(m)).

1, 2, 1, 2, 2, 11, 5, 2, 1, 2, 10, 11, 19, 13, 11, 11, 7, 11, 28, 2, 13, 10, 6, 11, 11, 19, 3, 13, 15, 11, 61, 13, 11, 8, 13, 11, 19, 28, 19, 2, 4, 13, 60, 10, 11, 12, 24, 11, 5, 11, 41, 19, 79, 82, 10, 13, 28, 15, 233, 11, 10, 61, 13, 17, 19, 11, 12, 8, 12, 13, 36, 11, 13, 19, 11, 37

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,2

COMMENTS

This sequence is well-defined.

LINKS

Table of n, a(n) for n=1..76.

Romanian Master in Mathematics Contest, Problem 3, Bucharest, 2007.

MATHEMATICA

spi[n_]:=Module[{m=1}, While[Mod[Floor[9^m/m], n]!=0, m++]; m]; Array[spi, 80] (* Harvey P. Dale, Jul 07 2022 *)

CROSSREFS

Cf. A129799, A138255, A138256, A138257, A138258, A138259, A138260, A138261, A138263.