Number of (n+1) X (1+1) 0..3 arrays with every 2 X 2 subblock summing to 6 and no 2 X 2 subblock having exactly two nonzero entries.

A251229

Number of (n+1) X (1+1) 0..3 arrays with every 2 X 2 subblock summing to 6 and no 2 X 2 subblock having exactly two nonzero entries.

Terms

    a(0) =38a(1) =110a(2) =322a(3) =966a(4) =2930a(5) =8982a(6) =27714a(7) =85958a(8) =267602a(9) =835574a(10) =2615266a(11) =8202150a(12) =25769714a(13) =81093846a(14) =255569538a(15) =806554502a(16) =2548769426a(17) =8064427958a(18) =25546995490a(19) =81022985574a(20) =257251995698a(21) =817658450070

External references