a(n) = a(1)*a(n-1) + a(2)*a(n-2) + ...+ a(n-1)*a(1) for n >= 2. Also a(n) = (2^n)*C(n-1), where C = A000108 (Catalan numbers).
A025225
a(n) = a(1)*a(n-1) + a(2)*a(n-2) + ...+ a(n-1)*a(1) for n >= 2. Also a(n) = (2^n)*C(n-1), where C = A000108 (Catalan numbers).
Terms
- a(0) =2a(1) =4a(2) =16a(3) =80a(4) =448a(5) =2688a(6) =16896a(7) =109824a(8) =732160a(9) =4978688a(10) =34398208a(11) =240787456a(12) =1704034304a(13) =12171673600a(14) =87636049920a(15) =635361361920
External references
- oeis: A025225