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A003125
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Value of an urn with n balls of type -1 and n+2 balls of type +1.
(Formerly M1929)
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2
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2, 9, 36, 142, 558, 2189, 8594, 33796, 133097, 524743, 2070466, 8177715, 32332378, 127948218, 506708043, 2007924808, 7960694208, 31576775077, 125313590701, 497543433995, 1976277486929, 7852859853208, 31214015140480, 124106224171554
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OFFSET
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1,1
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REFERENCES
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N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
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LINKS
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FORMULA
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A(m, p) = 0 for m < 0 or p < 0. A(0, 0) = 0. A(1, 0) = -1. A(0, 1) = 1. Otherwise, A(m, p) = A(m - 1, p) + A(m, p - 1).
B(m, p) = 0 for m < 0 or p < 0. Otherwise, B(m, p) = max{0, A(m, p) + B(m - 1, p) + B(m, p - 1)}.
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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