OFFSET
1,2
EXAMPLE
a(1) = (3*1+1/2-1/2)-(3*1-1) = 1;
a(2) = (3+3*2+1/2+1/2)-(2+3*2-1) = 3.
CROSSREFS
KEYWORD
nonn
AUTHOR
Juri-Stepan Gerasimov, Feb 01 2010
EXTENSIONS
Corrected (453 replaced by 493) by R. J. Mathar, May 22 2010
STATUS
approved