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A266772 Molien series for invariants of finite Coxeter group D_9. 0
1, 0, 1, 0, 2, 0, 3, 0, 5, 1, 7, 1, 11, 2, 15, 3, 22, 5, 30, 7, 41, 11, 54, 15, 73, 22, 94, 30, 123, 41, 157, 54, 201, 73, 252, 94, 318, 123, 393, 157, 488, 201, 598, 252, 732, 318, 887, 393, 1076, 488, 1291, 598, 1549, 732, 1845, 887, 2194, 1076, 2592, 1291, 3060, 1549, 3589, 1845, 4206, 2194, 4904, 2592, 5708, 3060, 6615, 3589 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,5

COMMENTS

The Molien series for the finite Coxeter group of type D_k (k >= 3) has G.f. = 1/Prod_i (1-x^(1+m_i)) where the m_i are [1,3,5,...,2k-3,k-1]. If k is even only even powers of x appear, and we bisect the sequence.

REFERENCES

J. E. Humphreys, Reflection Groups and Coxeter Groups, Cambridge, 1990. See Table 3.1, page 59.

LINKS

Table of n, a(n) for n=0..71.

Index entries for Molien series

FORMULA

G.f.: 1/((1-t^9)*(1-t^2)*(1-t^4)*(1-t^6)*(1-t^8)*(1-t^10)*(1-t^12)*(1-t^14)*(1-t^16)).

CROSSREFS

Molien series for finite Coxeter groups D_3 through D_12 are A266755, A266769, A266768, A003402, and A266770-A266775.

Sequence in context: A266774 A079977 A227093 * A262064 A008799 A325346

Adjacent sequences:  A266769 A266770 A266771 * A266773 A266774 A266775

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Jan 11 2016

STATUS

approved

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Last modified October 23 23:51 EDT 2019. Contains 328379 sequences. (Running on oeis4.)