OFFSET
1,1
COMMENTS
First differs from A022911 at n=18.
LINKS
Robert Israel, Table of n, a(n) for n = 1..10000
EXAMPLE
a(3) = 6 because A006987(3) = 15 = binomial(6,2).
MAPLE
CROSSREFS
KEYWORD
nonn
AUTHOR
Robert Israel, Sep 20 2018
STATUS
approved