143291610

Appears in sequences

• Super ballot numbers: 6(2n)!/(n!(n+2)!).at n=18A007054
• Catalan-like formula: a(n) = binomial(6*n, 3*n+1)/(9*n+6).at n=5A065424
• a(n) = 6*(2n-4)!/((n-2)!n!), if n>2. a(0) = 1, a(1) = a(2) = 2.at n=20A091712
• a(n) = 3/(n + 1) * Catalan(2*n).at n=9A387248