Number of independent sets of vertices in P_3 X C_n (n > 2).

Terms

a(0) =5a(1) =1a(2) =17a(3) =43a(4) =181a(5) =621a(6) =2309a(7) =8303a(8) =30277a(9) =109753a(10) =398857a(11) =1447931a(12) =5258725a(13) =19095285a(14) =69344061a(15) =251811903a(16) =914429445a(17) =3320635025a(18) =12058502657a(19) =43789003563a(20) =159014593621a(21) =577442573597