1,1
31 is the 11th prime. So 31 = sum{1<=k<=11,GCD(k,12)=1} a(k) = a(1)+a(5)+a(7)+a(11) = 2 +9 +3 +17.
Sequence in context: A058036 A136179 A185176 * A090559 A186725 A098570
Adjacent sequences: A126758 A126759 A126760 * A126762 A126763 A126764
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Leroy Quet Feb 22 2007