A097287 - OEIS

A097287

Rectangular array T by antidiagonals: T(n,k) = rank of n where (n,k) occurs in A097285, for distinct n,k and T(n,n)=0 for all n.

0, 1, 2, 3, 0, 6, 7, 5, 4, 12, 13, 9, 0, 8, 20, 21, 15, 11, 10, 14, 30, 31, 23, 17, 0, 16, 22, 42, 43, 33, 25, 19, 18, 24, 32, 56, 57, 45, 35, 27, 0, 26, 34, 44, 72, 73, 59, 47, 37, 29, 28, 36, 46, 58, 90, 91, 75, 61, 49, 39, 0, 38, 48, 60, 74, 110, 111, 93, 77, 63, 51, 41, 40, 50, 62

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OFFSET

1,3

COMMENTS

Every odd number occurs exactly once above the diagonal and every even, exactly once below the diagonal.

LINKS

Table of n, a(n) for n=1..75.

EXAMPLE

Northwest corner:

0 1 3 7 13

2 0 5 9 15

6 4 0 11 17