OFFSET
1,2
LINKS
Lars Blomberg, Table of n, a(n) for n = 1..55
N. J. A. Sloane and others, Sequences of RADD type, OEIS wiki.
CROSSREFS
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, May 06 2006
EXTENSIONS
a(9)-a(39) from Klaus Brockhaus, Jul 29 2006
STATUS
approved