A133239 Dimensions of certain Lie algebra (see reference for precise definition).

1, 78, 2430, 43758, 537966, 4969107, 36685506, 225961450, 1198006524, 5597569328, 23474156784, 89644484592, 315415779120, 1032380107812, 3168537039954, 9180278955210, 25252641533405, 66272502260250, 166635797864250, 402908157902250, 939815697512250

Offset

0,2

Links

Paolo Xausa, Table of n, a(n) for n = 0..10000

J. M. Landsberg and L. Manivel, The sextonions and E7 1/2, Adv. Math. 201 (2006), 143-179. [Th. 7.1, case a=2]

Maple

b:=binomial; t71:= proc(a, k) ((3*a+2*k+5)/(3*a+5)) * b(k+2*a+3, k)*b(k+5*a/2+3, k)*b(k+3*a+4, k)/(b(k+a/2+1, k)*b(k+a+1, k)); end; [seq(t71(2, k), k=0..30)];

Mathematica

t71[a_, k_] := (3a+2k+5) / (3a+5) Binomial[k+2a+3, k] Binomial[k+5/2a+3, k] Binomial[k+3a+4, k] / (Binomial[k+a/2+1, k] Binomial[k+a+1, k]);
Array[t71[2, #]&, 30, 0] (* Paolo Xausa, Jan 11 2024 *)

Crossrefs

Sequence in context: A036524 A262063 A140934 * A210407 A146479 A017794

Adjacent sequences: A133236 A133237 A133238 * A133240 A133241 A133242

Keyword

nonn

Author

N. J. A. Sloane, Oct 15 2007

Status

approved