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A279968
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Square array read by antidiagonals upwards in which each term is the number of prior elements in the same row, column, diagonal, or antidiagonal whose parity is not the same as the parity of n.
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2
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0, 0, 2, 0, 4, 0, 3, 1, 4, 2, 3, 3, 5, 3, 4, 2, 3, 5, 5, 4, 7, 2, 4, 5, 5, 6, 8, 3, 5, 4, 5, 10, 7, 7, 7, 7, 5, 5, 5, 9, 6, 12, 6, 8, 9, 4, 5, 8, 6, 6, 10, 9, 9, 7, 10, 4, 6, 8, 8, 5, 13, 9, 9, 12, 12, 8, 7, 6, 7, 8, 10, 9, 10, 12, 7, 11, 14, 9
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OFFSET
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1,3
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LINKS
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EXAMPLE
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The first six terms of this array are:
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0 2 0
0 4
0
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a(8) = 1 because the parity of 8 is different from the parity of a(7) = 1.
a(3) = 2 because the parity of 3 is different from the parity of a(2) = 0 and a(1) = 0.
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PROG
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(Haskell)
a279968 n = genericIndex a279968_list (n - 1)
a279968_list = map count [1..] where
count n = genericLength $ filter (odd . (n+)) adjacentLabels where
adjacentLabels = map a279968 (a274080_row n)
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CROSSREFS
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Cf. A279965 for the related sequence which counts same-parity prior elements.
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KEYWORD
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AUTHOR
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STATUS
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approved
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