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%I #2 Mar 30 2012 18:59:15
%S 1,1000000001,999999999000000001,1000000000000000000000000001,
%T 1000000001000000000000000001000000001,
%U 999999999000000001000000000999999999000000001
%N a(n)=A117611(9n).
%F a(n)=sum{k=0..9n, L(C(9n,k)/3)*10^k} where L(j/p) is the Legendre symbol of j and p.
%K easy,nonn
%O 0,2
%A _Paul Barry_, Apr 06 2006