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%I #11 Oct 07 2020 07:44:15
%S 1,6,11,36,66,121,216,396,726,1296,1331,2376,4356,7776,7986,14256,
%T 14641,26136,46656,47916,85536,87846,156816,161051,279936,287496,
%U 513216,527076,940896,966306,1679616,1724976,1771561,3079296,3162456
%N Numbers of the form (6^i)*(11^j), with i, j >= 0.
%H Reinhard Zumkeller, <a href="/A108698/b108698.txt">Table of n, a(n) for n = 1..10000</a>
%F Sum_{n>=1} 1/a(n) = (6*11)/((6-1)*(11-1)) = 33/25. - _Amiram Eldar_, Oct 07 2020
%F a(n) ~ exp(sqrt(2*log(6)*log(11)*n)) / sqrt(66). - _Vaclav Kotesovec_, Oct 07 2020
%t n = 10^6; Flatten[Table[6^i*11^j, {i, 0, Log[6, n]}, {j, 0, Log[11, n/6^i]}]] // Sort (* _Amiram Eldar_, Oct 07 2020 *)
%o (Haskell)
%o import Data.Set (singleton, deleteFindMin, insert)
%o a108698 n = a108698_list !! (n-1)
%o a108698_list = f $ singleton (1,0,0) where
%o f s = y : f (insert (6 * y, i + 1, j) $ insert (11 * y, i, j + 1) s')
%o where ((y, i, j), s') = deleteFindMin s
%o -- _Reinhard Zumkeller_, May 15 2015
%Y Cf. A025626, A025627, A025628, A025629, A064476, A107710, A003596, A003597, A107988, A003598, A108687, A003599, A107788, A108090.
%K nonn,easy
%O 1,2
%A Douglas Winston (douglas.winston(AT)srupc.com), Jun 19 2005
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