Number of planar cata-polyhexes with n cells.

Terms

a(0) =1a(1) =1a(2) =2a(3) =5a(4) =12a(5) =36a(6) =118a(7) =411a(8) =1489a(9) =5572a(10) =21115a(11) =81121a(12) =314075a(13) =1224528a(14) =4799205a(15) =18896981a(16) =74695032a(17) =296275836a(18) =1178741568a(19) =4702507923a(20) =18806505243a(21) =75380203150a(22) =302754225098