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.
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.
Terms
- a(0) =3a(1) =1a(2) =2a(3) =6a(4) =18a(5) =54a(6) =174a(7) =558a(8) =1782a(9) =5694a(10) =19170a(11) =64206a(12) =214050a(13) =712566a(14) =2465694a(15) =8480310a(16) =29012526a(17) =99157446a(18) =348577698a(19) =1219546278a(20) =4248000882a(21) =14773851366a(22) =52521676254a(23) =185880813822a(24) =655167175446
External references
- oeis: A024743