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(PARI) list(lim)=my(v=List(), N); for(n=0, logint(lim\=1, 10), N=10^n; while(N<=lim, listput(v, N); N*=9)); Set(v) \\ Charles R Greathouse IV, Jan 10 2018
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(Haskell)
import Data.Set (singleton, deleteFindMin, insert)
a025635 n = a025635_list !! (n-1)
a025635_list = f $ singleton (1, 0, 0) where
f s = y : f (insert (9 * y, i + 1, j) $ insert (10 * y, i, j + 1) s')
where ((y, i, j), s') = deleteFindMin s
-- Reinhard Zumkeller, May 15 2015
Reinhard Zumkeller, <a href="/A025635/b025635.txt">Table of n, a(n) for n = 1..10000</a>
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_David W. Wilson (davidwwilson(AT)comcast.net)_
easy,nonn,new
David W. Wilson (davidwwilson(AT)attbicomcast.comnet)
easy,huge,nonn,new
dww
David W. Wilson (davidwwilson(AT)attbi.com)
easy,huge,nonn,new
wilson@ctron.com
dww
Numbers of form 9^i*10^j, with i, j >= 0.
1, 9, 10, 81, 90, 100, 729, 810, 900, 1000, 6561, 7290, 8100, 9000, 10000, 59049, 65610, 72900, 81000, 90000, 100000, 531441, 590490, 656100, 729000, 810000, 900000, 1000000, 4782969, 5314410, 5904900, 6561000, 7290000, 8100000, 9000000
1,2
easy,huge,nonn
wilson@ctron.com
approved