A279965 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 the same as the parity of n.

0, 1, 1, 1, 3, 1, 2, 1, 5, 2, 2, 2, 5, 3, 4, 3, 4, 3, 8, 4, 4, 3, 5, 3, 7, 3, 9, 4, 4, 3, 8, 6, 6, 8, 6, 11, 4, 4, 8, 8, 5, 9, 7, 7, 7, 5, 6, 5, 6, 8, 8, 12, 9, 7, 8, 5, 7, 5, 7, 8, 12, 9, 13, 5, 15, 8, 6, 5, 10, 9, 6, 12, 8, 13, 11, 8, 12, 14

Offset

1,5

Links

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

Example

The array is constructed along its antidiagonals, in the following way:
.
a(1)  a(3)  a(6)  a(10)
a(2)  a(5)  a(9)
a(4)  a(8)
a(7)
.
----------------------------------------------------------
n       a(n)       array
----------------------------------------------------------
1       0          0
.
2       1          0
                   1
.
3       1          0 1
                   1
.
4       1          0 1
                   1
                   1
.
5       3          0 1
                   1 3
                   1
.
6       1          0 1 1
                   1 3
                   1
For example, a(5) = 3 because 5 has the same parity as a(2), a(3), and a(4), which are in the same row, column, and antidiagonal, respectively.

Crossrefs

Cf. A279968 for the similar array giving the number of prior elements of opposite parity.

Sequence in context: A347395 A059807 A214208 * A285121 A295935 A318323

Adjacent sequences: A279962 A279963 A279964 * A279966 A279967 A279968

Keyword

nonn,tabl

Author

Alec Jones, Dec 24 2016

Status

approved