-167772160domain: ZAppears in sequencesTriangle T, read by rows, where matrix power T^2 has 2*4^n in the secondary diagonal: [T^2](n+1,n) = 2*4^n, with all 1's in the main diagonal and zeros elsewhere.at n=23A117258a(0)=1. a(n) = 2^(n-2)*(5-n), for n>0.at n=25A172160