Number of n X 2 1..4 arrays with all 1's connected, all 2's connected, all 3's connected, all 4's 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 2 neighbors with the same value.
A164754
Number of n X 2 1..4 arrays with all 1's connected, all 2's connected, all 3's connected, all 4's 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 2 neighbors with the same value.
Terms
- a(0) =1a(1) =8a(2) =25a(3) =50a(4) =83a(5) =124a(6) =173a(7) =230a(8) =295a(9) =368a(10) =449a(11) =538a(12) =635a(13) =740a(14) =853a(15) =974a(16) =1103a(17) =1240a(18) =1385a(19) =1538a(20) =1699a(21) =1868a(22) =2045a(23) =2230a(24) =2423a(25) =2624a(26) =2833a(27) =3050a(28) =3275a(29) =3508
External references
- oeis: A164754