%I #3 Mar 30 2012 18:36:39
%S 1,2,4,9,23,67,220,795,3086,12633,53844,236833,1068313,4919512,
%T 23047579,109563206,527401808,2566472416,12608536729,62465984781,
%U 311796289951,1566778163225,7920718997762,40261922412697,205675725994566
%N Sum of first n terms of A(x)^n is A087457(n) for n>=1.
%C A087457 gives number of odd length roads between any adjacent nodes in virtual optimal chordal ring of degree 3.
%e Given a(1)=1 and a(1)=2, then a(2)=4 since sum of first 3 coefficients of
%e A(x)^3=1+6x+24x^2+... equals 1+6+24 = 31 = A087457(3).
%Y Cf. A087457, A088929.
%K nonn
%O 0,2
%A _Paul D. Hanna_, Oct 24 2003
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