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A239015 Exponents m such that the decimal expansion of 11^m exhibits its first zero from the right later than any previous exponent. 7
0, 1, 2, 3, 4, 6, 7, 8, 9, 12, 13, 14, 15, 16, 18, 36, 41, 366, 488, 4357, 69137, 89371, 143907, 542116, 2431369, 5877361, 8966861, 121915452, 123793821, 221788016, 709455085, 1571200127, 2640630712, 6637360862, 64994336645, 74770246842 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,3
COMMENTS
Assume that a zero precedes all decimal expansions. This will take care of those cases in A001020.
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 Wechsler and Franklin T. Adams-Watters.
LINKS
EXAMPLE
Illustration of initial term, with the 0 enclosed in parentheses:
n, position of 0, 11^a(n)
1, 2, (0)1
2, 3, (0)11
3, 4, (0)121
4, 5, (0)1331
5, 6, (0)14641
6, 7, (0)1771561
7, 8, (0)19487171
8, 9, (0)214358881
9, 10, (0)2357947691
10, 11, (0)3138428376721
11, 12, (0)34522712143931
12, 13, (0)379749833583241
13, 14, (0)4177248169415651
14, 15, (0)45949729863572161
15, 16, (0)5559917313492231481
16, 17, 3091268053287(0)672635673352936887453361
...
- N. J. A. Sloane, Jan 16 2020
MATHEMATICA
f[n_] := Position[ Reverse@ Join[{0}, IntegerDigits[ PowerMod[11, n, 10^500]]], 0, 1, 1][[1, 1]]; k = mx = 0; lst = {}; While[k < 40000001, c = f[k]; If[c > mx, mx = c; AppendTo[ lst, k]; Print@ k]; k++]; lst
CROSSREFS
Sequence in context: A330108 A330104 A330120 * A030706 A285986 A101883
KEYWORD
nonn,base,more
AUTHOR
EXTENSIONS
a(28)-a(34) from Bert Dobbelaere, Jan 22 2019
a(35)-a(36) from Chai Wah Wu, Jan 16 2020
STATUS
approved

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Last modified March 28 15:38 EDT 2024. Contains 371254 sequences. (Running on oeis4.)