A178695 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+x^17).

1, 0, 0, 1, 0, 1, 0, 1, 1, 1, 1, 1, 2, 1, 2, 2, 3, 2, 3, 2, 4, 3, 3, 4, 4, 5, 3, 6, 4, 6, 4, 6, 6, 6, 5, 6, 7, 5, 7, 5, 8, 5, 7, 5, 7, 6, 5, 6, 6, 6, 4, 6, 4, 6, 3, 5, 4, 4, 3, 3, 4, 2, 3, 2, 3, 2, 2, 1, 2, 1, 1, 1, 1, 1, 0, 1, 0, 1, 0, 0, 1

Offset

0,13

Comments

This is the Poincaré polynomial for the Lie group A_8.

References

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

Links

Table of n, a(n) for n=0..80.

Mathematica

CoefficientList[Series[Times@@(1+x^Range[3, 17, 2]), {x, 0, 80}], x] (* Harvey P. Dale, Jul 14 2014 *)

Crossrefs

A row of A142724.

Sequence in context: A272887 A143966 A260617 * A185315 A232548 A029363

Adjacent sequences: A178692 A178693 A178694 * A178696 A178697 A178698

Keyword

nonn,fini,full

Author

N. J. A. Sloane, Dec 25 2010

Status

approved