Number of primitive (period n) periodic palindromic structures using a maximum of three different symbols.

A056514

Number of primitive (period n) periodic palindromic structures using a maximum of three different symbols.

Terms

    a(0) =1a(1) =1a(2) =1a(3) =1a(4) =3a(5) =4a(6) =9a(7) =13a(8) =28a(9) =39a(10) =84a(11) =121a(12) =244a(13) =364a(14) =741a(15) =1088a(16) =2200a(17) =3280a(18) =6591a(19) =9841a(20) =19720a(21) =29510a(22) =59169a(23) =88573a(24) =177240a(25) =265716a(26) =531804a(27) =797121a(28) =1594684a(29) =2391484

External references