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A061987
Number of times n-th distinct value is repeated in sequence b(k) = 1 + b(floor(k/2)) + b(floor(k/3)) with b(0) = 0, i.e., in A061984; also number of times n-th distinct row is repeated in square array T(n,k) = T(n-1,k) + T(n-1,floor(k/2)) + T(n-1,floor(k/3)) with T(0,0) = 1, i.e., in A061980.
16
1, 1, 1, 1, 2, 2, 1, 3, 4, 2, 6, 3, 5, 4, 12, 6, 10, 8, 9, 15, 12, 20, 16, 18, 30, 24, 27, 13, 32, 36, 60, 48, 54, 26, 64, 72, 81, 39, 96, 108, 52, 128, 144, 162, 78, 192, 216, 104, 139, 117, 288, 324, 156, 384, 432, 208, 278, 234, 576, 648, 312, 417, 351, 864, 416, 556
OFFSET
0,5
COMMENTS
For n > 0: a(n) = A003586(n+1) - A003586(n) and a(A084791(n)) = A084788(n).
Also number of times A160519(n+1) is repeated in A088468. - Reinhard Zumkeller, May 16 2009
In the 14th century Levi Ben Gerson proved that a(n) > 1 for all n > 6; see A003586, A235365, A235366, A236210. - Jonathan Sondow, Jan 20 2014
LINKS
Eric Weisstein's World of Mathematics, Smooth Number
FORMULA
a(n) = A061986(A061985(n)).
PROG
(Haskell)
import Data.List (group)
a061987 n = a061987_list !! n
a061987_list = map length $ group a061984_list
-- Reinhard Zumkeller, Jan 11 2014
CROSSREFS
Sequence in context: A103923 A349432 A186711 * A323899 A182630 A208805
KEYWORD
nonn
AUTHOR
Henry Bottomley, May 24 2001
EXTENSIONS
More terms from Reinhard Zumkeller, Jun 03 2003
STATUS
approved