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%I #17 Sep 08 2022 08:46:11
%S 8,9,88,89,98,99,888,889,898,899,988,989,998,999,8888,8889,8898,8899,
%T 8988,8989,8998,8999,9888,9889,9898,9899,9988,9989,9998,9999,88888,
%U 88889,88898,88899,88988,88989,88998,88999,89888,89889
%N Numbers which have only digits 8 and 9 in base 10.
%H Vincenzo Librandi, <a href="/A256341/b256341.txt">Table of n, a(n) for n = 1..8190</a>
%H <a href="/index/Ar#10-automatic">Index entries for 10-automatic sequences</a>.
%F a(n) = A007931(n) + A002281(A000523(n+1)) = A256341(n) + A256077(n) etc.
%t Flatten[Table[FromDigits[#,10]&/@Tuples[{8,9},n],{n,5}]]
%o (Magma) [n: n in [1..35000] | Set(IntegerToSequence(n, 10)) subset {8, 9}];
%o (PARI) A256341(n)=vector(#n=binary(n+1)[2..-1],i,10^(#n-i))*n~+10^#n\9*8
%o (Magma) [n: n in [1..100000] | Set(Intseq(n)) subset {8,9}]; // _Vincenzo Librandi_, Aug 19 2016
%o (Python)
%o def a(n): return int(bin(n+1)[3:].replace('0', '8').replace('1', '9'))
%o print([a(n) for n in range(1, 45)]) # _Michael S. Branicky_, Aug 09 2021
%Y Cf. A007088 (digits 0 & 1), A007931 (digits 1 & 2), A032810 (digits 2 & 3), A032834 (digits 3 & 4), A256290 (digits 4 & 5) - A256292 (digits 6 & 7), A256340 (digits 7 & 8).
%K nonn,base,easy
%O 1,1
%A _M. F. Hasler_, Mar 27 2015
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