%I #7 Apr 09 2014 10:14:38
%S 1,1,2,3,4,5,4,6,8,9,5,8,6,11,7,6,16,17,9,13,11,19,13,11,15,18,23,17,
%T 14,26,28,14,32,33,19,26,20,33,21,15,23,29,37,26,18,40,41,19,28,47,37,
%U 46,47,50,49,50,37,25,55,57,33,35,34,34,64,65,39,51,41,57,43,31,45,54,61
%N a(1) = 1. For m >= 0 and 1 <= k <= 2^m, a(2^m +k) = number of earlier terms of the sequence which are coprime to a(k).
%e 8 = 2^2 + 4; so for a(8) we want the number of terms among terms a(1), a(2),... a(7) which are coprime to a(4) = 3. So a(8) = 6.
%o (PARI) A118577(mmax)= { local(a,ncopr); a=[1]; for(m=0,mmax, for(k=1,2^m, ncopr=0; for(i=1,2^m+k-1, if( gcd(a[k],a[i])==1, ncopr++; ); ); a=concat(a,ncopr); ); ); return(a); } { print(A118577(6)); } - _R. J. Mathar_, May 30 2006
%K nonn
%O 1,3
%A _Leroy Quet_, May 24 2006
%E More terms from _R. J. Mathar_, May 30 2006
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