a(n) = Sum_{k = 0..n} C(4*n + 1, 4*k).
A090407
a(n) = Sum_{k = 0..n} C(4*n + 1, 4*k).
Terms
- a(0) =1a(1) =6a(2) =136a(3) =2016a(4) =32896a(5) =523776a(6) =8390656a(7) =134209536a(8) =2147516416a(9) =34359607296a(10) =549756338176
External references
- oeis: A090407