Number of n X 2 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 4,2,2,0,2 for x=0,1,2,3,4.

A197642

Number of n X 2 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 4,2,2,0,2 for x=0,1,2,3,4.

Terms

    a(0) =1a(1) =2a(2) =11a(3) =31a(4) =66a(5) =185a(6) =595a(7) =1760a(8) =4857a(9) =13817a(10) =40388a(11) =117255a(12) =336113a(13) =965514a(14) =2786619a(15) =8042407a(16) =23164130a(17) =66711425a(18) =192263523a(19) =554192616a(20) =1596983385a(21) =4601566433a(22) =13260282324a(23) =38213747983a(24) =110121270385a(25) =317332109746a(26) =914453225419

External references