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A035848
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Coordination sequence for A_22 lattice.
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0
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1, 506, 64262, 3670018, 120177024, 2584888350, 39868752506, 468969729382, 4403475647758, 34183012888134, 225524301678170, 1292986222651646, 6559731002608432, 29893343687161218, 123905004120349254
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OFFSET
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0,2
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LINKS
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J. H. Conway and N. J. A. Sloane, Low-Dimensional Lattices VII: Coordination Sequences, Proc. Royal Soc. London, A453 (1997), 2369-2389 (pdf).
Index entries for linear recurrences with constant coefficients, signature (22, -231, 1540, -7315, 26334, -74613, 170544, -319770, 497420, -646646, 705432, -646646, 497420, -319770, 170544, -74613, 26334, -7315, 1540, -231, 22, -1).
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FORMULA
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Sum_{d=1..22} C(23, d)*C(m/2-1, d-1)*C(22-d+m/2, m/2), where norm m is always even.
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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Joan Serra-Sagrista (jserra(AT)ccd.uab.es)
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STATUS
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approved
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