Number of primitive (period n) periodic palindromes using a maximum of five different symbols.

A056496

Number of primitive (period n) periodic palindromes using a maximum of five different symbols.

Terms

    a(0) =5a(1) =10a(2) =20a(3) =60a(4) =120a(5) =340a(6) =620a(7) =1800a(8) =3100a(9) =9240a(10) =15620a(11) =46440a(12) =78120a(13) =233740a(14) =390480a(15) =1170000a(16) =1953120a(17) =5855900a(18) =9765620a(19) =29287440a(20) =48827480a(21) =146468740a(22) =244140620a(23) =732373200a(24) =1220703000a(25) =3662031240

External references