A084790 Increasing gaps between 3-smooth numbers (upper end).

2, 6, 12, 16, 24, 48, 96, 128, 192, 288, 324, 384, 576, 648, 729, 864, 972, 1152, 1296, 1458, 1728, 1944, 2592, 2916, 3456, 3888, 5184, 5832, 7776, 10368, 11664, 15552, 23328, 31104, 46656, 93312, 177147, 209952, 236196, 279936, 314928

Offset

1,1

Links

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

Formula

a(n) = A084788(n) + A084789(n).

a(n) = A003586(A084791(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[s[[1 + First@ Position[d, #]]] &, v] //Flatten (* Amiram Eldar, Jan 30 2020 *)

Crossrefs

Cf. A003586, A061987, A084788, A084789, A084791.

Sequence in context: A191331 A367465 A088915 * A130237 A053457 A299112

Adjacent sequences: A084787 A084788 A084789 * A084791 A084792 A084793

Keyword

nonn

Author

Reinhard Zumkeller, Jun 03 2003

Status

approved