[go: up one dir, main page]

login
A035894
Coordination sequence for diamond structure D^+_36. (Edges defined by l_1 norm = 1.)
1
1, 0, 2592, 0, 1121472, 0, 194986080, 0, 18300435840, 0, 1080041397408, 0, 44042615547456, 0, 1323529602867936, 0, 30721376739859200, 0, 570951082378155808, 1236950581248, 8740628929823039424
OFFSET
0,3
LINKS
J. H. Conway and N. J. A. Sloane, Low-Dimensional Lattices VII: Coordination Sequences, Proc. Royal Soc. London, A453 (1997), 2369-2389 (pdf).
Joan Serra-Sagrista, Enumeration of lattice points in l_1 norm, Inf. Proc. Lett. 76 (1-2) (2000) 39-44.
Index entries for linear recurrences with constant coefficients, signature (0, 36, 0, -630, 0, 7140, 0, -58905, 0, 376992, 0, -1947792, 0, 8347680, 0, -30260340, 0, 94143280, 0, -254186856, 0, 600805296, 0, -1251677700, 0, 2310789600, 0, -3796297200, 0, 5567902560, 0, -7307872110, 0, 8597496600, 0, -9075135300, 0, 8597496600, 0, -7307872110, 0, 5567902560, 0, -3796297200, 0, 2310789600, 0, -1251677700, 0, 600805296, 0, -254186856, 0, 94143280, 0, -30260340, 0, 8347680, 0, -1947792, 0, 376992, 0, -58905, 0, 7140, 0, -630, 0, 36, 0, -1).
MAPLE
f := proc(m) local k, t1; t1 := 2^(n-1)*binomial((n+2*m)/2-1, n-1); if m mod 2 = 0 then t1 := t1+add(2^k*binomial(n, k)*binomial(m-1, k-1), k=0..n); fi; t1; end; where n=36.
CROSSREFS
Sequence in context: A236351 A250241 A252152 * A179702 A258728 A326747
KEYWORD
nonn
AUTHOR
Joan Serra-Sagrista (jserra(AT)ccd.uab.es)
EXTENSIONS
Recomputed by N. J. A. Sloane, Nov 27 1998
STATUS
approved