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A084791
Where record gaps between 3-smooth numbers occur.
6
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
OFFSET
1,2
LINKS
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
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Jun 03 2003
STATUS
approved