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A097256 Numbers whose set of base 10 digits is {0,9}.

%I A097256 #16 Mar 04 2014 00:07:28
%S A097256 0,9,90,99,900,909,990,999,9000,9009,9090,9099,9900,9909,9990,9999,
%T A097256 90000,90009,90090,90099,90900,90909,90990,90999,99000,99009,99090,
%U A097256 99099,99900,99909,99990,99999,900000,900009,900090,900099,900900
%N A097256 Numbers whose set of base 10 digits is {0,9}.
%C A097256 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.
%H A097256 Reinhard Zumkeller, <a href="/A097256/b097256.txt">Table of n, a(n) for n = 0..10000</a>
%F A097256 a(n) = 9*A007088(n).
%F A097256 a(2n) = 10*a(n), a(2n+1) = a(2n)+9.
%p A097256 A097256:=n->(9/2) * add((1-(-1)^floor(n/2^i))*10^i, i=0..n); seq(A097256(n), n=0..30); # _Wesley Ivan Hurt_, Feb 11 2014
%t A097256 Table[(9/2) Sum[(1 - (-1)^Floor[n/2^i]) 10^i, {i, 0, n}], {n, 0, 30}] (* _Wesley Ivan Hurt_, Feb 11 2014 *)
%o A097256 (Haskell)
%o A097256 a097256 n = a097256_list !! n
%o A097256 a097256_list = map (* 9) a007088_list
%o A097256 -- _Reinhard Zumkeller_, Jan 10 2012
%Y A097256 Cf. A001196, A005823, A097251-A097262.
%Y A097256 Cf. A078248, A169965, A169966, A169967, A169964, A204093, A204094, A204095.
%K A097256 nonn,base
%O A097256 0,2
%A A097256 _Ray Chandler_, Aug 03 2004