OFFSET
1,2
EXAMPLE
Writing (i,j) for i+r*j, the first 7 in the ranking are
(0,0), (1,0), (0,1), (2,0), (1,1), (3,0), (0,2);
the ranks where i is odd are 2,5,6 and the ranks where
i is even are 1,3,4,7.
CROSSREFS
KEYWORD
nonn
AUTHOR
Clark Kimberling, Jan 08 2011
STATUS
approved