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A035058
Numbers k such that 2^k does not contain the digit 3 (probably finite).
2
0, 1, 2, 3, 4, 6, 7, 8, 9, 10, 11, 12, 13, 18, 19, 20, 21, 24, 26, 32, 34, 38, 40, 44, 48, 50, 53, 57, 60, 80, 91, 92, 102, 153
OFFSET
1,3
COMMENTS
No more terms <= 10^4. - Georg Fischer, Mar 12 2020
Next term > 2*10^5. - Tyler NeSmith, Jul 30 2021
MATHEMATICA
Join[{0}, Select[Range@10000, FreeQ[IntegerDigits[2^#], 3] &]] (* Vincenzo Librandi, May 07 2015 *)
PROG
(Magma) [n: n in [0..1000] | not 3 in Intseq(2^n) ]; // Vincenzo Librandi, May 07 2015
(PARI) isok(n) = ! vecsearch(Set(digits(2^n)), 3); \\ Michel Marcus, Feb 09 2018
CROSSREFS
Cf. similar sequences listed in A035064.
Sequence in context: A076216 A013919 A101771 * A350757 A004776 A187945
KEYWORD
nonn,base
AUTHOR
Patrick De Geest, Nov 15 1998
EXTENSIONS
Initial 0 added by Vincenzo Librandi, May 07 2015
Removed keyword "fini" as in A035064, since it is only a conjecture that this sequence contains only finitely many terms. - Georg Fischer, Mar 12 2020
STATUS
approved