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Number of terms in A145848 with exactly 2n decimal digits.
0

%I #13 Jan 27 2022 08:01:36

%S 1,1,5,1,12,1,24,2,47,2,53,1,70,1

%N Number of terms in A145848 with exactly 2n decimal digits.

%C It is shown by I. Bernshtein, see link, that a(2n+1)>=1 and 1<=a(2n)<=2. Thanks to Tanya Khovanova for this link.

%H I. Bernshtein, <a href="http://kvant.mccme.ru/1978/06/resheniya_zadachnika_kvanta_ma.htm">Solution of problem M460</a>.

%Y Cf. A145848, A146991.

%K more,nonn,base

%O 1,3

%A _Zak Seidov_, Nov 04 2008

%E Definition, comment, and a(11) corrected, and a(12)-a(14) added, by _Jon E. Schoenfield_, Nov 19 2008