Central terms in even-indexed rows of triangle A105556 and thus equals the n-th row sum of the n-th matrix power of the Narayana triangle A001263.
A105558
Central terms in even-indexed rows of triangle A105556 and thus equals the n-th row sum of the n-th matrix power of the Narayana triangle A001263.
Terms
- a(0) =1a(1) =2a(2) =12a(3) =148a(4) =3105a(5) =99156a(6) =4481449a(7) =272312216a(8) =21414443481
External references
- oeis: A105558