Number of nX4 1..4 arrays with all 1s connected, all 2s connected, all 3s connected, all 4s connected, 1 in the upper left corner, 2 in the upper right corner, 3 in the lower left corner, 4 in the lower right corner, and with no element having more than 3 neighbors with the same value.

A164761

Number of nX4 1..4 arrays with all 1s connected, all 2s connected, all 3s connected, all 4s connected, 1 in the upper left corner, 2 in the upper right corner, 3 in the lower left corner, 4 in the lower right corner, and with no element having more than 3 neighbors with the same value.

Terms

    a(0) =33a(1) =670a(2) =6549a(3) =45892a(4) =265155a(5) =1347918a(6) =6257643a(7) =27154502a(8) =111837041a(9) =441803872a(10) =1686870551a(11) =6260508940a(12) =22683215853a(13) =80510078988a(14) =280693737065a(15) =963421173780

External references