

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
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OFFSET

1,3


LINKS

Peter Kagey, Table of n, a(n) for n = 1..5000


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 sameparity prior elements.
Cf. also A279211, A279212.
Sequence in context: A239489 A259759 A119607 * A164297 A109578 A302826
Adjacent sequences: A279965 A279966 A279967 * A279969 A279970 A279971


KEYWORD

nonn,tabl


AUTHOR

Alec Jones, Dec 24 2016


STATUS

approved



