A025614 Numbers of form 3^i*6^j, with i, j >= 0.

1, 3, 6, 9, 18, 27, 36, 54, 81, 108, 162, 216, 243, 324, 486, 648, 729, 972, 1296, 1458, 1944, 2187, 2916, 3888, 4374, 5832, 6561, 7776, 8748, 11664, 13122, 17496, 19683, 23328, 26244, 34992, 39366, 46656, 52488, 59049, 69984, 78732, 104976, 118098

Offset

1,2

Links

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

Formula

Sum_{n>=1} 1/a(n) = (3*6)/((3-1)*(6-1)) = 9/5. - Amiram Eldar, Sep 26 2020

a(n) ~ exp(sqrt(2*log(3)*log(6)*n)) / sqrt(18). - Vaclav Kotesovec, Sep 26 2020

Mathematica

n = 10^6; Flatten[Table[3^i*6^j, {i, 0, Log[3, n]}, {j, 0, Log[6, n/3^i]}]] // Sort (* Amiram Eldar, Sep 26 2020 *)

Crossrefs

A025628 is a subsequence.

Cf. A003586, A003593, A003594, A003597, A107364.

Cf. A025610, A025618, A025622, A025626, A025627.

Sequence in context: A007783 A363128 A050625 * A182751 A057576 A100852

Adjacent sequences: A025611 A025612 A025613 * A025615 A025616 A025617

Keyword

easy,nonn

Author

David W. Wilson

Status

approved