OFFSET
1,1
EXAMPLE
a(1)=4-2=2, a(2)=6-4=2, a(3)=12-6=6.
CROSSREFS
KEYWORD
nonn
AUTHOR
Juri-Stepan Gerasimov, Nov 15 2009
EXTENSIONS
Corrected at 3 or more placed by R. J. Mathar, May 30 2010
STATUS
approved