From random walks on complete directed triangle.

Terms

a(0) =0a(1) =0a(2) =0a(3) =0a(4) =0a(5) =6a(6) =8a(7) =28a(8) =44a(9) =100a(10) =162a(11) =318a(12) =514a(13) =942a(14) =1518a(15) =2672a(16) =4302a(17) =7380a(18) =11882a(19) =20040a(20) =32276a(21) =53810a(22) =86710a(23) =143396a(24) =231204a(25) =380152a(26) =613286a(27) =1004188a(28) =1620864a(29) =2645928