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

A056517

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

Terms

    a(0) =1a(1) =1a(2) =1a(3) =1a(4) =3a(5) =4a(6) =10a(7) =14a(8) =36a(9) =50a(10) =138a(11) =202a(12) =561a(13) =875a(14) =2571a(15) =4105a(16) =12548a(17) =20647a(18) =65456a(19) =109298a(20) =356466a(21) =601476a(22) =2005341a(23) =3403126a(24) =11522216a(25) =19628059a(26) =67182654a(27) =114700263a(28) =395494722a(29) =676207627

External references