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%I #13 Dec 30 2017 03:40:38
%S 0,1,2,4,3,9,4,10,7,5,16,18,11,21,8,6,15,17,20,14,19,13,12,42,89,7,76,
%T 18,21,95,80,34,13,43,24,90,65,51,8,86,77,19,32,22,49,47,96,98,81,35,
%U 100,14,73,83,44,70,25,91,28,66,37,59,52,102,9,87,16,78,41,75
%N a(n) is the least nonnegative exponent k such that 2^k ends in A095810(n).
%H Robert Israel, <a href="/A293779/b293779.txt">Table of n, a(n) for n = 1..10000</a>
%F n = 6: A095810(6) = 12. k = 9 is the least nonnegative integer such that 2^k ends in 12. Therefore, a(6) = 9.
%p # assuming A095810[1]..A095810[N] are assigned
%p f:= proc(i) local s,v,t;
%p s:= msolve(2^x=A095810[i],10^(1+ilog10(A095810[i])));
%p v:= indets(rhs(s[1]),name);
%p if v <> {} then subs(seq(t=0,t=v),rhs(s[1])) else rhs(s[1]) fi
%p end proc:
%p map(f, [$1..N]); # _Robert Israel_, Dec 29 2017
%Y Cf. A095810.
%K nonn,base
%O 1,3
%A _David A. Corneth_, Oct 17 2017