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A279968
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.
2
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
OFFSET
1,3
EXAMPLE
The first six terms of this array are:
.
0 2 0
0 4
0
.
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.
PROG
(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)
CROSSREFS
Cf. A279965 for the related sequence which counts same-parity prior elements.
Cf. also A279211, A279212.
Sequence in context: A259759 A364817 A119607 * A164297 A349240 A366879
KEYWORD
nonn,tabl
AUTHOR
Alec Jones, Dec 24 2016
STATUS
approved