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A084788 Sizes of successive increasing gaps between 3-smooth numbers. 6
1, 2, 3, 4, 6, 12, 15, 20, 30, 32, 36, 60, 64, 72, 81, 96, 108, 128, 144, 162, 192, 216, 288, 324, 384, 432, 576, 648, 864, 1152, 1296, 1728, 2592, 3456, 5184, 10368, 11259, 13344, 15012, 17792, 20016, 22518, 26688, 30024, 40032, 45036, 53376 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

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

Eric Weisstein's World of Mathematics, Smooth Number

FORMULA

a(n) = A084790(n) - A084789(n).

a(n) = A061987(A084791(n)).

MATHEMATICA

s = {}; m = 13; Do[n = 3^k; While[n <= 3^m, AppendTo[s, n]; n*=2], {k, 0, m}]; DeleteDuplicates @ FoldList[Max, Differences @ Union[s]] (* Amiram Eldar, Jan 30 2020 *)

CROSSREFS

Cf. A003586, A061987, A084789, A084790, A084791.

Sequence in context: A128393 A057919 A102250 * A002809 A015904 A015888

Adjacent sequences:  A084785 A084786 A084787 * A084789 A084790 A084791

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Jun 03 2003

STATUS

approved

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Last modified November 28 16:42 EST 2021. Contains 349413 sequences. (Running on oeis4.)