A024743 a(n) = Sum_{i=1..floor((n+1)/4)} a(2*i-1) * a(n-2*i+1), with a(1)=3, a(2)=1, and a(3)=2.

3, 1, 2, 6, 18, 54, 174, 558, 1782, 5694, 19170, 64206, 214050, 712566, 2465694, 8480310, 29012526, 99157446, 348577698, 1219546278, 4248000882, 14773851366, 52521676254, 185880813822, 655167175446, 2306629089486, 8261570136834, 29484704469390

Offset

1,1

Links

Table of n, a(n) for n=1..28.

Crossrefs

Sequence in context: A308709 A166197 A010279 * A024963 A283435 A212737

Adjacent sequences: A024740 A024741 A024742 * A024744 A024745 A024746

Keyword

nonn

Author

Clark Kimberling

Status

approved