Kekulé numbers for certain benzenoids.

Terms

a(0) =1a(1) =36a(2) =448a(3) =3175a(4) =15786a(5) =61446a(6) =199872a(7) =566676a(8) =1441275a(9) =3356782a(10) =7268976a(11) =14805583a(12) =28621684a(13) =52892100a(14) =93977088a(15) =161303616a(16) =268510869a(17) =434915472a(18) =687359200a(19) =1062509679a(20) =1609692766a(21) =2394343930a(22) =3502175040a(23) =5044162500