434685788658domain: NAppears in sequencesTriangle T, read by rows, where matrix power T^3 has powers of 3 in the secondary diagonal: [T^3](n+1,n) = 3^(n+1), with all 1's in the main diagonal and zeros elsewhere.at n=28A117252Column 0 of triangle A117252.at n=7A117253a(n) = (1/3!)*3^(n+1)*(n+5)*(n+1)*(n).at n=16A288836