Number of n X 2 0..1 arrays with each 1 adjacent to 2, 3 or 4 king-move neighboring 1s.

A296821

Number of n X 2 0..1 arrays with each 1 adjacent to 2, 3 or 4 king-move neighboring 1s.

Terms

    a(0) =1a(1) =6a(2) =21a(3) =56a(4) =178a(5) =609a(6) =1997a(7) =6511a(8) =21494a(9) =71021a(10) =234110a(11) =771936a(12) =2546839a(13) =8401997a(14) =27715289a(15) =91426922a(16) =301604833a(17) =994943072a(18) =3282138566a(19) =10827217153a(20) =35717165621a(21) =117824839843a(22) =388684058778

External references