Number of walks of length n between two nodes at distance 3 in the cycle graph C_7.

Terms

a(0) =1a(1) =1a(2) =5a(3) =6a(4) =21a(5) =28a(6) =84a(7) =121a(8) =331a(9) =507a(10) =1300a(11) =2093a(12) =5110a(13) =8568a(14) =20129a(15) =34885a(16) =79477a(17) =141494a(18) =314489a(19) =572264a(20) =1246784a(21) =2309385a(22) =4950751a(23) =9303411a(24) =19684692a(25) =37427313a(26) =78354346a(27) =150402700a(28) =312168761a(29) =603861897