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A173389
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A shifted symmetrical triangular sequence:t(n,m)=If[Mod[n, 2] == 0, Binomial[n, m], Binomial[n - 1, m - 1] + If[(n - 3)*(m - 2) >= 1, Binomial[n - 3, m - 2], 0]]
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0
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1, 0, 1, 1, 2, 1, 0, 1, 2, 1, 1, 4, 6, 4, 1, 0, 1, 4, 8, 5, 1, 1, 6, 15, 20, 15, 6, 1, 0, 1, 6, 19, 26, 19, 7, 1, 1, 8, 28, 56, 70, 56, 28, 8, 1, 0, 1, 8, 34, 71, 90, 71, 34, 9, 1, 1, 10, 45, 120, 210, 252, 210, 120, 45, 10, 1
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OFFSET
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0,5
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COMMENTS
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Row sums are: {1, 1, 4, 4, 16, 19, 64, 79, 256, 319, 1024,...}.
The sequence is designed to be symmetrical with every other row shifted to the right and a symmetrical term added to is so that the row sums aren't the same.
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LINKS
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FORMULA
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t(n,m)=If[Mod[n, 2] == 0, Binomial[n, m], Binomial[n - 1, m - 1] + If[(n - 3)*(m - 2) >= 1, Binomial[n - 3, m - 2], 0]]
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EXAMPLE
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{1},
{0, 1},
{1, 2, 1},
{0, 1, 2, 1},
{1, 4, 6, 4, 1},
{0, 1, 4, 8, 5, 1},
{1, 6, 15, 20, 15, 6, 1},
{0, 1, 6, 19, 26, 19, 7, 1},
{1, 8, 28, 56, 70, 56, 28, 8, 1},
{0, 1, 8, 34, 71, 90, 71, 34, 9, 1},
{1, 10, 45, 120, 210, 252, 210, 120, 45, 10, 1}
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MATHEMATICA
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t[n_, m_] = If[Mod[n, 2] == 0, Binomial[n, m], Binomial[n - 1, m - 1] + If[(n - 3)*(m - 2) >= 1, Binomial[n - 3, m - 2], 0]];
Table[Table[t[n, m], {m, 0, n}], {n, 0, 10}];
Flatten[%]
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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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