Kekulé numbers for certain benzenoids.

Terms

a(0) =1a(1) =22a(2) =193a(3) =1045a(4) =4180a(5) =13566a(6) =37764a(7) =93456a(8) =210705a(9) =440440a(10) =864721a(11) =1610401a(12) =2866864a(13) =4908580a(14) =8123280a(15) =13046616a(16) =20404233a(17) =31162242a(18) =46587145a(19) =68316325a(20) =98440276a(21) =139597810a(22) =195085540a(23) =268983000a(24) =366294825a(25) =493111476a(26) =656790057