%I #7 Jul 26 2019 06:37:27
%S 0,1,2,2,8,9,26,28,88,89,292,297,994,1001,3418,3430,11920,11934,41944,
%T 41990,149184,149221,534756,534888,1931394,1931540,7019976,7020391,
%U 25662396,25662825,94285650,94287120,347992480,347993868
%N Isomers of polyenes attached to benzene (see Cyvin et al. for precise definition).
%H B. N. Cyvin, E. Brendsdal, J. Brunvoll and S. J. Cyvin, <a href="https://hrcak.srce.hr/176546">Isomers of polyenes attached to benzene</a>, Croatica Chemica Acta, 68 (1995), 63-73, M(x).
%p U0 := (1-sqrt(1-4*x))/2/x ;
%p V0 := 1+x*subs(x=x^2,U0) ;
%p Mb := ( subs(x=x^2,U0)^3 -subs(x=x^4,U0)*subs(x=x^2,V0) -subs(x=x^6,U0) +subs(x=x^6,V0) )/2 ; # (20)
%p Ma := ( subs(x=x^2,U0)^2*V0^2 -subs(x=x^3,V0)^2 -subs(x=x^4,U0)*subs(x=x^2,V0) +subs(x=x^6,V0) )/2 ; # (21)
%p M := Mb+Ma ;
%p taylor(%,x=0,40) ;
%p gfun[seriestolist](%) ; # _R. J. Mathar_, Jul 26 2019
%K nonn
%O 0,3
%A _N. J. A. Sloane_, Aug 11 2006