OFFSET
0,15
COMMENTS
a(n) is also the number of simply-connected semisimple Lie groups.
Is a(n) eventually monotonically increasing, and if so, beyond what index?
EXAMPLE
a(3) = 1 since A_1 is the only semisimple Lie algebra of dimension 3.
For n=21, the a(21) = 5 such Lie algebras are A_1+A_1+A_1+A_1+A_1+A_1+A_1, A_1+A_1+A_3, A_1+A_2+B_2, B_3, and C_3
CROSSREFS
KEYWORD
nonn
AUTHOR
Andrew Rupinski, Jan 11 2011
STATUS
approved