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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.

%I A279968 #23 Dec 27 2016 13:09:56
%S A279968 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,
%T A279968 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,
%U A279968 8,7,6,7,8,10,9,10,12,7,11,14,9
%N 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.
%H A279968 Peter Kagey, <a href="/A279968/b279968.txt">Table of n, a(n) for n = 1..5000</a>
%e A279968 The first six terms of this array are:
%e A279968 .
%e A279968 0 2 0
%e A279968 0 4
%e A279968 0
%e A279968 .
%e A279968 a(8) = 1 because the parity of 8 is different from the parity of a(7) = 1.
%e A279968 a(3) = 2 because the parity of 3 is different from the parity of a(2) = 0 and a(1) = 0.
%o A279968 (Haskell)
%o A279968 a279968 n = genericIndex a279968_list (n - 1)
%o A279968 a279968_list = map count [1..] where
%o A279968   count n = genericLength $ filter (odd . (n+)) adjacentLabels where
%o A279968     adjacentLabels = map a279968 (a274080_row n)
%Y A279968 Cf. A279965 for the related sequence which counts same-parity prior elements.
%Y A279968 Cf. also A279211, A279212.
%K A279968 nonn,tabl
%O A279968 1,3
%A A279968 _Alec Jones_, Dec 24 2016