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%I #17 Oct 05 2021 16:06:09
%S 10,5,4,3,2,2,2,2,2,10,10,9,8,8,7,7,6,6,6,5,5,5,5,5,4,4,4,4,4,4,4,4,4,
%T 3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,
%U 2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,10,10,10
%N Least positive integer m such that m*n has greater decimal digit length than n.
%C For any positive base B >= 2 the corresponding sequence contains only terms from 2 to B inclusive so the corresponding sequence for binary is all 2s (A007395).
%H Michael S. Branicky, <a href="/A097327/b097327.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = A097326(n) + 1.
%F a(n) = ceiling(10^A055642(n)/n). - _Michael S. Branicky_, Oct 05 2021
%e a(12) = 9 since 12 has two decimal digits and 9*12 = 108 has three (but 8*12 = 96 has only two).
%o (Python)
%o def a(n): return (10**len(str(n))-1)//n + 1
%o print([a(n) for n in range(1, 103)]) # _Michael S. Branicky_, Oct 05 2021
%o (PARI) a(n) = my(m=1, sn=#Str(n)); while (#Str(m*n) <= sn, m++); m; \\ _Michel Marcus_, Oct 05 2021
%Y Cf. A089186 (analog for decimal m+n), A080079 (analog for binary m+n), A097326.
%Y Cf. A055642.
%K base,easy,nonn
%O 1,1
%A _Rick L. Shepherd_, Aug 04 2004
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