A025622 - OEIS

A025622

Numbers of form 5^i*6^j, with i, j >= 0.

1, 5, 6, 25, 30, 36, 125, 150, 180, 216, 625, 750, 900, 1080, 1296, 3125, 3750, 4500, 5400, 6480, 7776, 15625, 18750, 22500, 27000, 32400, 38880, 46656, 78125, 93750, 112500, 135000, 162000, 194400, 233280, 279936, 390625, 468750, 562500, 675000

(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) = (5*6)/((5-1)*(6-1)) = 3/2. - Amiram Eldar, Sep 25 2020

a(n) ~ exp(sqrt(2*log(5)*log(6)*n)) / sqrt(30). - Vaclav Kotesovec, Sep 25 2020

MATHEMATICA

n = 10^6; Flatten[Table[5^i*6^j, {i, 0, Log[5, n]}, {j, 0, Log[6, n/5^i]}]] // Sort (* Amiram Eldar, Sep 25 2020 *)

CROSSREFS

Cf. A000351 (subset), A000400 (another subset).

Sequence in context: A033042 A039594 A137080 * A116553 A249222 A034497

Adjacent sequences: A025619 A025620 A025621 * A025623 A025624 A025625

KEYWORD

easy,nonn

AUTHOR

David W. Wilson

STATUS

approved