Number of reversible strings with n-1 beads of 2 colors. 5 beads are black. String is not palindromic.

A032092

Number of reversible strings with n-1 beads of 2 colors. 5 beads are black. String is not palindromic.

Terms

    a(0) =3a(1) =9a(2) =28a(3) =60a(4) =126a(5) =226a(6) =396a(7) =636a(8) =1001a(9) =1491a(10) =2184a(11) =3080a(12) =4284a(13) =5796a(14) =7752a(15) =10152a(16) =13167a(17) =16797a(18) =21252a(19) =26532a(20) =32890a(21) =40326a(22) =49140a(23) =59332a(24) =71253a(25) =84903a(26) =100688a(27) =118608a(28) =139128a(29) =162248

External references