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A179683
The dimension of the space of invariant tensors in the n-th tensor power of the adjoint representation of the exceptional Lie algebra E7.
2
1, 0, 1, 1, 5, 16, 80, 436, 2877, 21828, 189877, 1865175, 20468437, 248376198, 3303397123, 47785692843, 746841034620, 12538089887528, 224955746518560, 4294093811333388, 86859002770470072, 1855099612560598420, 41698660497526383757
OFFSET
0,5
COMMENTS
This is known to satisfy a linear recurrence relation with polynomial coefficients. The limit of a(n+1)/a(n) is 133.
LINKS
EXAMPLE
The n-th tensor power is the trivial representation for n=0 and is the adjoint representation for n=1. For n=2 every invariant tensor is a scalar multiple of a Killing form.
CROSSREFS
Sequence in context: A179663 A372174 A227292 * A179685 A286077 A286072
KEYWORD
nonn
AUTHOR
Bruce Westbury, Jul 24 2010
EXTENSIONS
More terms from Bruce Westbury, Nov 08 2013
STATUS
approved