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

A056513

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

Terms

    a(0) =1a(1) =1a(2) =1a(3) =1a(4) =2a(5) =3a(6) =4a(7) =7a(8) =10a(9) =14a(10) =21a(11) =31a(12) =42a(13) =63a(14) =91a(15) =123a(16) =184a(17) =255a(18) =371a(19) =511a(20) =750a(21) =1015a(22) =1519a(23) =2047a(24) =3030a(25) =4092a(26) =6111a(27) =8176a(28) =12222a(29) =16383

External references