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A035840
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Coordination sequence for A_14 lattice.
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1
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1, 210, 11130, 269570, 3838590, 37060506, 265953170, 1511679210, 7125357540, 28818500830, 102644594262, 328512273390, 959882556570, 2593322651430, 6545498596110, 15564971674518
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OFFSET
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0,2
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REFERENCES
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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.
J. Serra-Sagrista, Enumeration of lattice points in l_1 norm, Information Processing Letters, 76, no. 1-2 (2000), 39-44.
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LINKS
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Table of n, a(n) for n=0..15.
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).
Index to sequences with linear recurrences with constant coefficients, signature (14,-91,364,-1001,2002,-3003,3432,-3003,2002,-1001,364,-91,-14,1]).
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FORMULA
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Sum_{d=1}^14 C(15, d) C(m/2-1, d-1) C(14-d+m/2, m/2), where norm m is always even
G.f.: (x^14 +196*x^13 +8281*x^12 +132496*x^11 +1002001*x^10 +4008004*x^9 +9018009*x^8 +11778624*x^7 +9018009*x^6 +4008004*x^5 +1002001*x^4 +132496*x^3 +8281*x^2 +196*x +1) / (x -1)^14. [Colin Barker, Nov 19 2012]
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CROSSREFS
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Sequence in context: A087977 A185042 A023905 * A140904 A092711 A187308
Adjacent sequences: A035837 A035838 A035839 * A035841 A035842 A035843
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KEYWORD
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nonn,easy
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AUTHOR
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Serra-Sagrista, Joan; jserra(AT)ccd.uab.es
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STATUS
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approved
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