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A035064
Numbers n such that 2^n does not contain the digit 9 (probably finite).
10
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 14, 15, 16, 17, 18, 19, 20, 23, 24, 25, 26, 27, 28, 30, 31, 45, 46, 47, 57, 58, 59, 71, 77, 99, 108
OFFSET
1,3
EXAMPLE
Here is 2^108, conjecturally the largest power of 2 that does not contain a 9:
324518553658426726783156020576256. - N. J. A. Sloane, Feb 10 2023
MATHEMATICA
Join[{0}, Select[Range@ 1000, FreeQ[IntegerDigits[2^#], 9] &]] (* Vincenzo Librandi, May 06 2015 *)
PROG
(Magma) [n: n in [0..1000] | not 9 in Intseq(2^n) ]; // Vincenzo Librandi, May 06 2015
CROSSREFS
Cf. numbers n such that decimal expansion of 2^n contains no k: A007377 (k=0), A035057 (k=1), A034293 (k=2), A035058 (k=3), A035059 (k=4), A035060 (k=5), A035061 (k=6), A035062 (k=7), A035063 (k=8), this sequence (k=9).
Sequence in context: A048336 A130574 A023780 * A113191 A191923 A191922
KEYWORD
nonn,base
AUTHOR
Patrick De Geest, Nov 15 1998
EXTENSIONS
Initial 0 added by Vincenzo Librandi, May 06 2015
Removed keyword "fini" at the suggestion of Nathan Fox, since it is only a conjecture that this sequence contains only finitely many terms. - N. J. A. Sloane, Mar 03 2016
STATUS
approved