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A097415 Values of k such that the first digit of 2^k is 9. 6
53, 63, 73, 83, 93, 156, 166, 176, 186, 249, 259, 269, 279, 289, 352, 362, 372, 382, 445, 455, 465, 475, 485, 548, 558, 568, 578, 641, 651, 661, 671, 734, 744, 754, 764, 774, 837, 847, 857, 867, 930, 940, 950, 960, 970, 1033, 1043, 1053, 1063, 1126 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
The asymptotic density of this sequence is 1 - log_10(9) = 0.045757... (A104140). - Amiram Eldar, Jan 27 2021
LINKS
Eric Weisstein's World of Mathematics, Gelfand's Question.
MATHEMATICA
Select[Range[1200], IntegerDigits[2^#][[1]]==9&] (* Harvey P. Dale, Nov 30 2019 *)
CROSSREFS
Sequence in context: A102635 A036268 A326169 * A061946 A039531 A369101
KEYWORD
nonn,base
AUTHOR
Eric W. Weisstein, Aug 16 2004
STATUS
approved

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Last modified March 29 08:13 EDT 2024. Contains 371265 sequences. (Running on oeis4.)