A084791 - OEIS

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A084791

Where record gaps between 3-smooth numbers occur.

1, 4, 7, 8, 10, 14, 19, 21, 24, 28, 29, 30, 34, 35, 36, 38, 39, 41, 42, 43, 45, 46, 50, 51, 53, 54, 58, 59, 63, 67, 68, 72, 78, 82, 88, 99, 110, 113, 115, 118, 120, 122, 125, 127, 133, 135, 138, 140, 146, 148, 154, 160, 162, 168, 175, 176, 177, 183, 190, 191, 192

(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

A084788(n) = A061987(a(n)).

A084789(n) = A003586(a(n)).

A084790(n) = A003586(a(n) + 1).

MATHEMATICA

s = {}; m = 13; Do[n = 3^k; While[n <= 3^m, AppendTo[s, n]; n*=2], {k, 0, m}]; s = Union[s]; d = Differences@s; v = DeleteDuplicates @ FoldList[Max, d]; Map[First@ Position[d, #] &, v] //Flatten (* Amiram Eldar, Jan 30 2020 *)

CROSSREFS

Cf. A003586, A084788, A084789, A084790.

Sequence in context: A175008 A336408 A286401 * A310933 A186712 A001494

Adjacent sequences: A084788 A084789 A084790 * A084792 A084793 A084794

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Jun 03 2003

STATUS

approved