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A239014
Exponents m such that the decimal expansion of 9^m exhibits its first zero from the right later than any previous exponent.
7
0, 2, 3, 4, 6, 7, 12, 13, 14, 17, 26, 34, 68, 406, 926, 2227, 3379, 3824, 26364, 197564, 9669757, 11470439, 15754533, 18945654, 25742286, 38175282, 237545304, 320907073, 2928221215, 3653563322, 5788579994, 25722005323, 30228962873, 137527721034, 217558664165, 523648850797
OFFSET
1,2
COMMENTS
Assume that a zero precedes all decimal expansions. This will take care of those cases in A030705.
Inspired by the seqfan list discussion Re: "possible sequence", beginning with David Wilson 7:57 PM Mar 06 2014 and continued by M. F. Hasler, Allan C. Wechsler and Franklin T. Adams-Watters.
Not just two time A001019.
MATHEMATICA
f[n_] := Position[ Reverse@ Join[{0}, IntegerDigits[ PowerMod[9, n, 10^500]]], 0, 1, 1][[1, 1]]; k = mx = 0; lst = {}; While[k < 10000001, c = f[k]; If[c > mx, mx = c; AppendTo[ lst, k]; Print@ k]; k++]; lst
CROSSREFS
Except for its second term, A030705 is a subsequence.
Sequence in context: A091336 A002235 A217132 * A030705 A305929 A057128
KEYWORD
nonn,base
EXTENSIONS
a(27)-a(31) from Bert Dobbelaere, Jan 21 2019
a(32)-a(36) from Chai Wah Wu, Jan 13 2020
STATUS
approved