A138261 Smallest positive integer m such that n divides [8^m/m] (=A129798(m)).

1, 1, 10, 1, 3, 10, 7, 1, 11, 3, 21, 11, 9, 9, 13, 2, 3, 11, 13, 9, 11, 21, 15, 11, 21, 9, 13, 9, 10, 13, 11, 2, 21, 3, 9, 11, 13, 13, 17, 9, 21, 11, 10, 21, 13, 15, 92, 55, 29, 21, 20, 9, 58, 13, 21, 9, 13, 10, 22, 13, 21, 11, 11, 4, 9, 21, 23, 9, 67, 9, 46, 11, 13, 13, 21, 13, 31, 17

Offset

1,3

Comments

This sequence is well-defined.

Links

Table of n, a(n) for n=1..78.

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

Formula

If A138255(n) is divisible by 3 then a(n)=A138255(n)/3. In general, a(n) >= A138255(n)/3.

Mathematica

spi[n_]:=Module[{m=1}, While[!Divisible[Floor[8^m/m], n], m++]; m]; Array[spi, 80] (* Harvey P. Dale, Oct 23 2022 *)

Crossrefs

Cf. A129798, A138255, A138256, A138257, A138258, A138259, A138260, A138262, A138263.

Sequence in context: A366165 A010181 A111525 * A068126 A156225 A284327

Adjacent sequences: A138258 A138259 A138260 * A138262 A138263 A138264

Keyword

nonn

Author

Max Alekseyev, Mar 09 2008.

Status

approved