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%I #25 Jan 04 2016 02:18:38
%S 3,14,61,263,1128,4788,20271,85885,364408,1546394,6563924,27863816,
%T 118286561
%N Number of n-digit numbers that are divisible by a square and have the same property if any number of rightmost digits is deleted.
%C See A237607 for the numbers themselves and for more comments.
%C The ratio r(n) = a(n+1)/a(n) seems to converge to a constant value of about 4.245...
%H Stanislav Sykora, <a href="https://oeis.org/wiki/File:GeneticThreads.txt">PARI/GP scripts for genetic threads</a>
%e One-digit numbers k with moebius(k)=0 are 4, 8 and 9. Hence a(1) = 3.
%o (PARI) See the link (use GT_DivMod0 with "IsMoebiusZero" for the "property" argument).
%Y Cf. A237607.
%K nonn,hard,more,base
%O 1,1
%A _Stanislav Sykora_, Feb 15 2014
%E a(12)-a(13) from _Lars Blomberg_, Jan 02 2016
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