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A050148
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a(n) = T(n,n-2), array T as in A050143.
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2
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1, 7, 32, 160, 832, 4424, 23872, 130176, 715520, 3957448, 21998176, 122786976, 687736896, 3863423880, 21758302848, 122811081216, 694533774336, 3934558067336, 22323615621280, 126832567223712, 721500116473664
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OFFSET
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2,2
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COMMENTS
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Also T(2*n-2,n-2), array T as in A055807.
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LINKS
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FORMULA
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a(n) = Sum_{s=1..n} binomial(n,s)*binomial(s+n-4,n-3) = n*hypergeom([-n + 1, n-2], [2], -1) for n >= 3. - Petros Hadjicostas, Feb 13 2021
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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