a(n) = Sum_{k=0..n-3} T(n,k) * T(n,k+3), with T given by A026758.
A027234
a(n) = Sum_{k=0..n-3} T(n,k) * T(n,k+3), with T given by A026758.
Terms
- a(0) =1a(1) =9a(2) =62a(3) =320a(4) =1837a(5) =8376a(6) =45666a(7) =198471a(8) =1065418a(9) =4523403a(10) =24247545a(11) =101589616a(12) =547233490a(13) =2273356598a(14) =12341618508a(15) =50963502172a(16) =279167141052
External references
- oeis: A027234