Number of black-square subarrays of (n+2) X (4+2) 0..3 arrays x(i,j) with each element diagonally or antidiagonally next to at least one element with value (x(i,j)+1) mod 4, no adjacent elements equal, and upper left element zero.

A230931

Number of black-square subarrays of (n+2) X (4+2) 0..3 arrays x(i,j) with each element diagonally or antidiagonally next to at least one element with value (x(i,j)+1) mod 4, no adjacent elements equal, and upper left element zero.

Terms

    a(0) =8a(1) =48a(2) =232a(3) =1242a(4) =6896a(5) =37984a(6) =208172a(7) =1142054a(8) =6269172a(9) =34409586a(10) =188850410a(11) =1036485334a(12) =5688689754a(13) =31221981876a(14) =171359511448a(15) =940494098820

External references