1,2
Row 2 gives the Catalan numbers, which automatically makes row 3 interesting.
Table of n, a(n) for n=1..7.
Cf. A000108, A211400.
Sequence in context: A188899 A052203 A027331 * A091161 A135149 A269007
Adjacent sequences: A255486 A255487 A255488 * A255490 A255491 A255492
nonn,more
N. J. A. Sloane, Mar 01 2015
approved
