Number of squarefree words of length 5 in an (n+1)-ary alphabet.

Terms

a(0) =0a(1) =30a(2) =264a(3) =1140a(4) =3480a(5) =8610a(6) =18480a(7) =35784a(8) =64080a(9) =107910a(10) =172920a(11) =265980a(12) =395304a(13) =570570a(14) =803040a(15) =1105680a(16) =1493280a(17) =1982574a(18) =2592360a(19) =3343620a(20) =4259640a(21) =5366130a(22) =6691344a(23) =8266200a(24) =10124400a(25) =12302550a(26) =14840280a(27) =17780364a(28) =21168840a(29) =25055130