A131513 A123689 based sequence as SO(A123689(n)) dimensions.

0, 1, 6, 45, 120, 325, 496, 1035, 1770, 2701, 3828, 5778, 7626, 10585, 14706, 18721, 23220, 30628, 37950, 47278

Offset

1,3

Comments

Related to the D_n Cartan like even groups that are like exceptional groups

Links

Table of n, a(n) for n=1..20.

Formula

a(n) = A123689(n)*(A123689(n)-1)/2

Mathematica

(*A123689*) a = {0, 2, 4, 10, 16, 26, 32, 46, 60, 74, 88, 108, 124, 146, 172, 194, 216, 248, 276, 308} Table[a[[n]]*(a[[n]] - 1)/2, {n, 1, Length[a]}]

Crossrefs

Cf. A123689.

Sequence in context: A063947 A006086 A273507 * A204558 A354477 A123141

Adjacent sequences: A131510 A131511 A131512 * A131514 A131515 A131516

Keyword

nonn,uned

Author

Roger L. Bagula, Aug 14 2007

Status

approved