OFFSET
1,1
EXAMPLE
Writing (i,j) for i+j/r, the first 7 in the ranking are (0,0), (0,1), (1,0), (0,2), (1,1), (2,0), (0,3); the ranks where i is odd are 3,5 and the ranks where i is even are 1,2,4,6,7.
CROSSREFS
KEYWORD
nonn
AUTHOR
Clark Kimberling, Jan 13 2011
STATUS
approved