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A238892
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Index of last squarefree number in the first half of row n of Pascal's triangle.
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2
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0, 0, 1, 1, 2, 2, 2, 3, 4, 0, 4, 5, 2, 4, 6, 6, 0, 8, 0, 9, 8, 9, 10, 11, 4, 5, 10, 0, 10, 11, 2, 10, 0, 1, 16, 3, 0, 4, 18, 18, 4, 9, 10, 18, 20, 12, 18, 20, 0, 0, 0, 1, 16, 21, 18, 10, 0, 21, 22, 23, 28, 29, 30, 9, 0, 1, 2, 3, 32, 33, 6, 35, 0, 9, 32, 10, 36
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OFFSET
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0,5
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COMMENTS
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The first squarefree binomial coefficient in every row is at position 0. Sequence A048279 lists the rows n for which a(n) = 0.
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LINKS
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MATHEMATICA
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Table[Position[Binomial[n, Range[0, n/2]], _?(SquareFreeQ[#] &)][[-1, 1]] - 1, {n, 0, 100}]
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CROSSREFS
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Cf. A238337 (number of distinct squarefree numbers in row n).
Cf. A238891 (last squarefree number in the first half of row n).
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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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