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A178692 Expansion of the polynomial (1+x^3)*(1+x^5)*(1+x^7)*(1+x^9)*(1+x^11)*(1+x^13)*(1+x^15). 1

%I #9 Jun 11 2018 13:59:18

%S 1,0,0,1,0,1,0,1,1,1,1,1,2,1,2,2,3,1,3,2,3,3,2,4,3,4,2,5,3,4,3,4,4,3,

%T 4,3,5,2,4,3,4,2,3,3,2,3,1,3,2,2,1,2,1,1,1,1,1,0,1,0,1,0,0,1

%N Expansion of the polynomial (1+x^3)*(1+x^5)*(1+x^7)*(1+x^9)*(1+x^11)*(1+x^13)*(1+x^15).

%C This is the Poincaré polynomial for the Lie group A_7.

%D Borel, A. and Chevalley, C., The Betti numbers of the exceptional groups, Mem. Amer. Math. Soc. 1955, no. 14, pp 1-9.

%t CoefficientList[Expand[Times@@(1+x^Range[3,15,2])],x] (* _Harvey P. Dale_, Jun 11 2018 *)

%Y A row of A142724.

%K nonn,fini,full

%O 0,13

%A _N. J. A. Sloane_, Dec 25 2010

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