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A035721
Coordination sequence for 26-dimensional cubic lattice.
1
1, 52, 1352, 23452, 305552, 3191812, 27866072, 209284972, 1381251872, 8143343572, 43450388072, 212064570172, 955155127472, 4000059761572, 15676069223672, 57810425102092, 201600442152512, 667669374615412
OFFSET
0,2
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 (26, -325, 2600, -14950, 65780, -230230, 657800, -1562275, 3124550, -5311735, 7726160, -9657700, 10400600, -9657700, 7726160, -5311735, 3124550, -1562275, 657800, -230230, 65780, -14950, 2600, -325, 26, -1).
FORMULA
G.f.: ((1+x)/(1-x))^26.
For n >= 1, a(n) = (4/3698160658676859375)*k*(4*k^24 +5200*k^22 +2696980*k^20 +729500200*k^18 +113058092290*k^16 +10403235809200*k^14 +571033266394960*k^12 +18358560436559200*k^10 +331670354541689020*k^8 +3134604254001277200*k^6 +13742418871540936746*k^4 +22474514386734286500*k^2 +8373940585251924375). - Robert Israel, Oct 21 2016
n*a(n) = 52*a(n-1) + (n-2)*a(n-2) for n > 1. - Seiichi Manyama, Aug 21 2018
MATHEMATICA
CoefficientList[Series[((1+x)/(1-x))^26, {x, 0, 20}], x] (* Harvey P. Dale, Mar 19 2017 *)
CROSSREFS
Sequence in context: A130000 A160153 A017768 * A035798 A017715 A112008
KEYWORD
nonn,easy
AUTHOR
Joan Serra-Sagrista (jserra(AT)ccd.uab.es)
EXTENSIONS
Recomputed by N. J. A. Sloane, Nov 25 1998
STATUS
approved