Number of ways to tile a double-hexagon strip of n hexagons, using single and double hexagons.

Terms

a(0) =1a(1) =1a(2) =2a(3) =4a(4) =8a(5) =12a(6) =24a(7) =48a(8) =72a(9) =144a(10) =288a(11) =432a(12) =864a(13) =1728a(14) =2592a(15) =5184a(16) =10368a(17) =15552a(18) =31104a(19) =62208a(20) =93312a(21) =186624a(22) =373248a(23) =559872a(24) =1119744a(25) =2239488a(26) =3359232a(27) =6718464a(28) =13436928a(29) =20155392