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%I #7 Apr 09 2014 10:14:39
%S 1,1,2,3,4,4,6,7,6,9,10,7,12,11,8,15,16,11,18,17,11,18,22,15,21,25,16,
%T 24,28,16,30,31,16,32,25,23,36,37,25,32,40,25,42,39,23,43,46,32,43,40,
%U 34,50,52,38,39,50,39,57,58,32,60,60,39,63,45,38,66,65,41,47,70,47,72
%N a(1)=1. a(n) = number of earlier terms which are coprime to the largest odd divisor of n.
%e The largest odd divisor of 12 is 3. So a(12) is the number of terms from among (a(1),a(2),...a(11)) which are coprime to 3, which is 7.
%p lod:=proc(n) if n mod 2 = 1 then n else lod(n/2) fi end: seq(lod(n),n=1..100): a[1]:=1: for n from 2 to 100 do a[n]:=0: for j from 1 to n-1 do if igcd(a[j],lod(n))=1 then a[n]:=1+a[n] else fi od: od: seq(a[n],n=1..100); # lod finds the largest odd divisor - _Emeric Deutsch_, May 22 2007
%Y Cf. A130044, A000265.
%K nonn
%O 1,3
%A _Leroy Quet_, May 02 2007
%E More terms from _Emeric Deutsch_, May 22 2007
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