%I A118230
%S A118230 0,0,1,1,0,0,1,2,0,1,1,1,2,1,1,0,2,2,1,0,0,1,1,1,4,2,1,1,0,0,1,0,2,6,3,
%T A118230 0,6,7,1,2,8,8,5,5,2,12,3,7,6,9,1,18,6,21,9,5,4,25,1,1,2,39,1,35,0,3,3,
%U A118230 18,22,37,5,5,8,48,9,45,10,4,5,55,10,40,17,35,4,2,11,61,4,13
%V A118230 0,0,1,-1,0,0,-1,2,0,-1,1,-1,-2,1,1,0,2,-2,-1,0,0,1,1,-1,-4,2,1,1,0,0,
               1,0,2,-6,3,0,-6,
%W A118230 7,1,-2,8,-8,-5,-5,-2,12,3,-7,-6,-9,1,18,6,-21,-9,-5,4,25,-1,1,2,-39,-1,
               35,0,3,3,-18,
%X A118230 -22,37,5,-5,8,-48,9,45,-10,-4,5,-55,10,40,-17,-35,4,-2,-11,61,4,-13
%N A118230 Column 3 of triangle A118229, starting with row 1 to include leading 
               zeros.
%H A118230 Leroy Quet, <a href="http://www.prism-of-spirals.net/">Home Page</a> 
               (listed in lieu of email address)
%F A118230 Sum_{k=1..n, gcd(n,k)=1} a(k) = 1 when n=4, 0 elsewhere.
%o A118230 (PARI) {a(n)=(matrix(n+2,n+2,r,c,if(r>=c,if(gcd(r-c+1,c)==1,1,0)))^-1)[n,
               3]}
%Y A118230 Cf. A118229.
%Y A118230 Sequence in context: A099494 A030341 A121444 this_sequence A153246 A025889 
               A126306
%Y A118230 Adjacent sequences: A118227 A118228 A118229 this_sequence A118231 A118232 
               A118233
%K A118230 sign
%O A118230 1,8
%A A118230 Leroy Quet, Paul D. Hanna (pauldhanna(AT)juno.com), Apr 16 2006