27246964
domain: N
Appears in sequences
- a(n) = 4*a(n-1) - a(n-2) with a(0) = 2, a(1) = 4.at n=13A003500
- Arises from generalized Lucas-Lehmer test for primality.at n=10A018844
- Array T(n,k) read by antidiagonals: T(n,k) = sum(i=0...n, (-1)^(n+i) * C(n+i,2i) * n/(2i+1) * k^(2i+1) ), n>0, k>1.at n=30A231123
- Sides of (Heronian) triangles where sides are consecutive integers and area is an integer.at n=37A242497