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a(n)=sum_{k=1..n} r(k) where r(k)=A000002(k) if A000002(k+1)=2 and r(k)=0 if A000002(k+1)=1
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%I #2 Mar 30 2012 18:39:28

%S 1,3,3,3,4,4,5,7,7,8,10,10,10,11,11,11,12,14,14,15,15,15,16,16,17,19,

%T 19,19,20,20,20,21,21,22,24,24,25,27,27,27,28,28,29,31,31,32,32,32,33,

%U 33,33,34,36,36,37,39,39,39,40,40,41,43,43,44,46,46,46,47,47,47,48,48,49

%N a(n)=sum_{k=1..n} r(k) where r(k)=A000002(k) if A000002(k+1)=2 and r(k)=0 if A000002(k+1)=1

%K nonn

%O 1,2

%A _Benoit Cloitre_, Feb 08 2009