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 A084789 Increasing gaps between 3-smooth numbers (lower end). 6
 1, 4, 9, 12, 18, 36, 81, 108, 162, 256, 288, 324, 512, 576, 648, 768, 864, 1024, 1152, 1296, 1536, 1728, 2304, 2592, 3072, 3456, 4608, 5184, 6912, 9216, 10368, 13824, 20736, 27648, 41472, 82944, 165888, 196608, 221184, 262144, 294912, 331776 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Amiram Eldar, Table of n, a(n) for n = 1..10000 FORMULA a(n) = A084790(n) - A084788(n). a(n) = A003586(A084791(n)). 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[[First@ Position[d, #]]] &, v] //Flatten (* Amiram Eldar, Jan 30 2020 *) CROSSREFS Cf. A003586, A061987, A084788, A084790, A084791. Sequence in context: A312865 A348918 A181023 * A157650 A312866 A312867 Adjacent sequences:  A084786 A084787 A084788 * A084790 A084791 A084792 KEYWORD nonn AUTHOR Reinhard Zumkeller, Jun 03 2003 STATUS approved

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Last modified December 1 16:44 EST 2021. Contains 349430 sequences. (Running on oeis4.)