A025628 - OEIS

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A025628

Numbers of form 6^i*9^j, with i, j >= 0.

1, 6, 9, 36, 54, 81, 216, 324, 486, 729, 1296, 1944, 2916, 4374, 6561, 7776, 11664, 17496, 26244, 39366, 46656, 59049, 69984, 104976, 157464, 236196, 279936, 354294, 419904, 531441, 629856, 944784, 1417176, 1679616, 2125764, 2519424, 3188646

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

OFFSET

1,2

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..10000

FORMULA

Sum_{n>=1} 1/a(n) = (6*9)/((6-1)*(9-1)) = 27/20. - Amiram Eldar, Sep 26 2020

a(n) ~ exp(sqrt(2*log(6)*log(9)*n)) / sqrt(54). - Vaclav Kotesovec, Sep 26 2020

MATHEMATICA

n = 10^6; Flatten[Table[6^i*9^j, {i, 0, Log[6, n]}, {j, 0, Log[9, n/6^i]}]] // Sort (* Amiram Eldar, Sep 26 2020 *)

CROSSREFS

Subsequence of A025614.