1937768448

Appears in sequences

• Triangle T, read by rows, where matrix power T^-2 has -2^(n+1) in the secondary diagonal: [T^-2](n+1,n) = -2^(n+1), with all 1's in the main diagonal and zeros elsewhere.at n=38A117265
• a(n) = n*(n-1)*2^n.at n=22A128796