Number of 2Xn 0..1 arrays with every element equal to 0, 2, 3 or 4 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.

A302368

Number of 2Xn 0..1 arrays with every element equal to 0, 2, 3 or 4 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.

Terms

    a(0) =2a(1) =2a(2) =12a(3) =20a(4) =72a(5) =168a(6) =496a(7) =1296a(8) =3616a(9) =9760a(10) =26816a(11) =73024a(12) =199808a(13) =545408a(14) =1490688a(15) =4071680a(16) =11125248a(17) =30392832a(18) =83037184a(19) =226857984a(20) =619792384a(21) =1693296640a(22) =4626182144a(23) =12638949376a(24) =34530271232a(25) =94338424832a(26) =257737408512

External references