Number of nX2 0..1 arrays with every element unequal to 1, 2 or 4 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.

A317857

Number of nX2 0..1 arrays with every element unequal to 1, 2 or 4 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.

Terms

    a(0) =1a(1) =3a(2) =6a(3) =10a(4) =21a(5) =46a(6) =102a(7) =220a(8) =491a(9) =1077a(10) =2393a(11) =5271a(12) =11682a(13) =25799a(14) =57090a(15) =126209a(16) =279123a(17) =617274a(18) =1364930a(19) =3018713a(20) =6675002a(21) =14762294a(22) =32643544a(23) =72191407a(24) =159639957a(25) =353036505a(26) =780698639a(27) =1726457594a(28) =3817890631a(29) =8442936930

External references