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A097256
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Numbers whose set of base 10 digits is {0,9}.
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10
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0, 9, 90, 99, 900, 909, 990, 999, 9000, 9009, 9090, 9099, 9900, 9909, 9990, 9999, 90000, 90009, 90090, 90099, 90900, 90909, 90990, 90999, 99000, 99009, 99090, 99099, 99900, 99909, 99990, 99999, 900000, 900009, 900090, 900099, 900900
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,2
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COMMENTS
| n such that there exists a permutation p_1, ..., p_n of 1, ..., n such that i + p_i is a power of 10 for every i.
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LINKS
| Reinhard Zumkeller, Table of n, a(n) for n = 0..10000
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FORMULA
| a(n) = 9*A007088(n).
a(2n) = 10*a(n), a(2n+1) = a(2n)+9.
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PROG
| (Haskell)
a097256 n = a097256_list !! n
a097256_list = map (* 9) a007088_list
-- Reinhard Zumkeller, Jan 10 2012
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CROSSREFS
| Cf. A001196, A005823, A097251-A097262.
Cf. A078248, A169965, A169966, A169967, A169964, A204093, A204094, A204095.
Sequence in context: A078248 A186943 A121029 * A061478 A061878 A140160
Adjacent sequences: A097253 A097254 A097255 * A097257 A097258 A097259
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KEYWORD
| nonn,base
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AUTHOR
| Ray Chandler (rayjchandler(AT)sbcglobal.net), Aug 3 2004
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