|
Search: id:A008397
|
|
|
| A008397 |
|
Coordination sequence for E_7 lattice. |
|
+0
3
|
|
| 1, 126, 2898, 25886, 133506, 490014, 1433810, 3573054, 7902594, 15942206, 29896146, 52834014, 88892930, 143501022, 223622226, 338022398, 497556738, 715478526, 1007769170, 1393489566
(list; graph; listen)
|
|
|
OFFSET
|
0,2
|
|
|
REFERENCES
|
R. Bacher, P. de la Harpe and B. Venkov, Series de croissance et series d'Ehrhart associees aux reseaux de racines, C. R. Acad. Sci. Paris, 325 (Series 1) (1997), 1137-1142.
|
|
LINKS
|
T. D. Noe, Table of n, a(n) for n=0..1000
J. H. Conway and N. J. A. Sloane, Low-Dimensional Lattices VII: Coordination Sequences, Proc. Royal Soc. London, A453 (1997), 2369-2389 (Abstract, pdf, ps).
|
|
FORMULA
|
a(n) = 148/5*n^6-12/5*n^5+52*n^4+12*n^3+212/5*n^2-48/5*n+2.
Bacher et al. give a g.f.
|
|
MAPLE
|
148/5*n^6-12/5*n^5+52*n^4+12*n^3+212/5*n^2-48/5*n+2;
|
|
CROSSREFS
|
Sequence in context: A109146 A133499 A113857 this_sequence A086024 A036403 A140902
Adjacent sequences: A008394 A008395 A008396 this_sequence A008398 A008399 A008400
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
njas and J. H. Conway (conway(AT)math.princeton.edu)
|
|
|
Search completed in 0.002 seconds
|
