This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A239013 #26 Jan 22 2020 14:46:13
%S A239013 0,2,3,5,6,8,9,11,12,13,17,24,27,43,144,342,633,653,2642,6966,16124,
%T A239013 84595,225177,4069057,4890280,6298187,39573326,99250579,242281125,
%U A239013 1007075831,4705063695,5439666500,5741331846,6168193506,9297912451,34411164318,36390662612,265816303567
%N A239013 Exponents m such that the decimal expansion of 8^m exhibits its first zero from the right later than any previous exponent.
%C A239013 Assume that a zero precedes all decimal expansions. This will take care of those cases in A030704.
%C A239013 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_.
%C A239013 Not just three times A031142; although {99250579, 6168193506, 9297912451, 34411164318, 36390662612} are possible candidates.
%t A239013 f[n_] := Position[ Reverse@ Join[{0}, IntegerDigits[ PowerMod[8, n, 10^500]]], 0, 1, 1][[1, 1]]; k = mx = 0; lst = {}; While[k < 200000001, c = f[k]; If[c > mx, mx = c; AppendTo[ lst, k]; Print@ k]; k++]; lst
%Y A239013 Cf. A001018, A030704, A020665, A031142, A239008, A239009, A239010, A239011, A239012, A239014, A239015.
%K A239013 nonn,base
%O A239013 1,2
%A A239013 _Charles R Greathouse IV_ and _Robert G. Wilson v_, Mar 14 2014
%E A239013 a(29)-a(35) from _Bert Dobbelaere_, Jan 21 2019
%E A239013 a(36)-a(38) from _Chai Wah Wu_, Jan 18 2020