OFFSET
0,3
COMMENTS
A succession is a pair of cells (v, v+1) lying in the same row.
Also number of ballot sequences of length 2n having exactly n flat steps.
FORMULA
a(n) = A238125(2n,n).
CROSSREFS
KEYWORD
nonn
AUTHOR
Joerg Arndt and Alois P. Heinz, Apr 28 2014
STATUS
approved