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A178930
Number of semisimple Lie algebras of dimension n.
0
0, 0, 0, 1, 0, 0, 1, 0, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 3, 2, 3, 5, 3, 4, 8, 4, 5, 8, 7, 8, 11, 10, 11, 12, 13, 15, 19, 16, 21, 24, 21, 24, 32, 27, 34, 43, 37, 39, 53, 47, 54, 65, 65, 68, 79, 80, 90, 98, 102, 114, 129, 122, 138, 160, 157, 172, 207, 193, 211, 247, 244, 262, 306, 305, 329, 363, 378, 399, 448, 460
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
Sequence in context: A366580 A088019 A301508 * A126759 A293444 A302791
KEYWORD
nonn
AUTHOR
Andrew Rupinski, Jan 11 2011
STATUS
approved