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A099608
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Table of crystal ball sequences for A_n lattices read by antidiagonals.
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1
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1, 1, 1, 1, 3, 1, 1, 5, 7, 1, 1, 7, 19, 13, 1, 1, 9, 37, 55, 21, 1, 1, 11, 61, 147, 131, 31, 1, 1, 13, 91, 309, 471, 271, 43, 1, 1, 15, 127, 561, 1251, 1281, 505, 57, 1, 1, 17, 169, 923, 2751, 4251, 3067, 869, 73, 1, 1, 19, 217, 1415, 5321, 11253, 12559, 6637, 1405, 91, 1
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OFFSET
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0,5
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COMMENTS
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Rows (n=0..10) are A000012, A005408, A003215, A005902, A008384, A008386, A008388, A008390, A008392, A008394, A008396.
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LINKS
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FORMULA
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T(n, k)=hypergeom([n+1, -n, -k], [1, 1], 1).
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PROG
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(PARI) T(n, k)=sum(j=0, min(n, k), binomial(n+j, j)*binomial(n, j)*binomial(k, j))
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CROSSREFS
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KEYWORD
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AUTHOR
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STATUS
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approved
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