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A109441 A sequence of Cartan group dimensions, sorted and duplicates deleted: Dim{A_n,B_n,C_n,D_n}={(n + 1)^2 - 1, (2*n + 1)*(2*n + 1 - 1)/2, (2*n)^2, (2*n)*(2*n - 1)/2}. 1
0, 1, 3, 4, 6, 8, 10, 15, 16, 21, 24, 28, 35, 36, 45, 48, 55, 63, 64, 66, 78, 80, 91, 99, 100, 105, 120, 136, 143, 144, 153, 168, 171, 190, 195, 196, 210, 224, 231, 253, 255, 256, 276, 300, 324, 325, 351, 378, 400, 406, 435, 465, 484, 576, 676, 784, 900 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Result gives new exceptional groups isomorphisms: E_6->D_6 ( 78) E_7 1/2-> D_9 ( 190) E_9(E_11 ?)-> C_10 ( 484) And none for G_2,F_4,E_7,E_8. (14,52,133,248) That reasoning separates the exception groups into two types.

REFERENCES

R. N. Cahn, Semi-Simple Lie Algebras and Their Representations, Dover, NY, 2006, ISBN 0-486-44999-8, p. 139.

Todd Rowland, "Dynkin Diagram", http://mathworld.wolfram.com/DynkinDiagram.html

LINKS

Table of n, a(n) for n=1..57.

FORMULA

A_n->Dim_SL(n+1)=(n+1)^2-1 B_n->Dim_SO(2*n+1)=(2*n+1)*(2*n+1-1)/2 C_n->Dim_SP(2*n)=((2*n)^2 D_n->Dim_SO(2*n)=2*n*(2*n-1)/2 a(n)=Sort[{(n + 1)^2 - 1, (2*n + 1)*(2*n + 1 - 1)/2, (2*n)^2, (2*n)*(2*n - 1)/2}]

MATHEMATICA

Union[Flatten[Table[{(n + 1)^2 - 1, (2*n + 1)*(2*n + 1 - 1)/2, (2*n)^2, (2*n)*(2*n - 1)/2}, {n, 0, 15}]]]

CROSSREFS

Cf. A120722.

Sequence in context: A173339 A064269 A120150 * A176986 A069357 A080728

Adjacent sequences:  A109438 A109439 A109440 * A109442 A109443 A109444

KEYWORD

nonn,uned

AUTHOR

Roger L. Bagula, Jun 22 2007

STATUS

approved

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Last modified May 24 14:54 EDT 2013. Contains 225624 sequences.