OFFSET
1,3
EXAMPLE
Triangle begins:
1,1,
4,1,2,3,
7,1,2,3,4,5,
10,1,2,3,4,5,6,7,
13,1,2,3,4,5,6,7,8,9,
16,1,2,3,4,5,6,7,8,9,10,11,
19,1,2,3,4,5,6,7,8,9,10,11,12,13,
22,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,
25,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,
CROSSREFS
KEYWORD
easy,nonn,tabf
AUTHOR
Omar E. Pol, Feb 23 2010
STATUS
approved