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%I #6 Oct 21 2013 07:35:31
%S 10,99,1090,11880,129601,1413720,15421330,168220899,1835008570,
%T 20016873360,218350598401,2381839709040,25981886201050,
%U 283418908502499,3091626107326450,33724468272088440,367877524885646401,4012928305470021960,43774333835284595170,477504743882660524899,5208777848873981178730
%N a(n) = A006190(n) * A006190(n+2).
%C 1/3 = 3/10 + 3/99 + 3/1090, + 3/11880 + ..., = 3/(1*10) + 3/(3*33) + 3/(10*109) + 3/(33*360) + ...
%C Odd n terms == 1 mod 9; even n terms == 0 mod 9
%F a(n) = A006190(n) * A006190(n+2).
%F Empirical g.f.: -x*(x-10) / ((x+1)*(x^2-11*x+1)). - _Colin Barker_, Oct 20 2013
%e a(3) = A006190(3) * A006190(5) = 10 * 109 = 1090
%Y Cf. A006190.
%K nonn
%O 1,1
%A _Gary W. Adamson_, Mar 16 2008
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