OFFSET
1,3
EXAMPLE
1; 1,2; 1,4,2; 1,6,6,8; 1,8,12,16,8; ...
CROSSREFS
T(n, k) = number of paths from (0, 0) to (n, n-k) in the directed graph having vertices (i, j) for i >= 0, j >= 0 and edges as follows: for i >= 0, j >= 0, the unit square ABCD labeled counterclockwise from vertex A=(i, j) has directed edges AB, DC, AD, BC and also AC and DB if i and j are both even.
KEYWORD
nonn,tabl
AUTHOR
STATUS
approved