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A226951
Number of filiform Lie algebras with a certain grading of dimension n over Z_2.
1
1, 1, 2, 4, 4, 6, 6, 10, 10, 16, 14, 20, 18, 26, 20, 32, 28, 36, 32, 44, 40, 56, 46, 56, 54, 74, 60, 82, 64, 84, 68, 86, 74, 100, 84, 106, 92, 114, 98, 126, 104, 126, 112, 138, 122, 156, 134, 152, 140, 170, 142, 172, 152, 194, 176, 188, 170, 222, 196, 232, 184
OFFSET
4,3
COMMENTS
Let G = <X_1,X_2,...,X_n> be a filiform Lie algebra of dimension n over Z_2. Define the grading [X_i,X_j]=c_(i,j)X_(i+j), for i,j >=2 for some constants c_(i,j) in Z_2. How many such algebras there exist on dimension n? The sequence gives us up to a point this numbers starting with dimension four, that is, there exists only one such an algebra with dimension four, 1 again with dimension 5, 2 with dimension 6 and so forth.
LINKS
Grant Cairns, Ana Hinić Galić, and Yuri Nikolayevsky, Totally geodesic subalgebras of nilpotent Lie algebras, arxiv.org 1112.1288
John Tsartsaflis, Maple implementation
CROSSREFS
Sequence in context: A164798 A087554 A281072 * A251557 A231901 A135974
KEYWORD
nonn
AUTHOR
John Tsartsaflis, Jun 24 2013
STATUS
approved