Number of quinary sequences of length n such that no two consecutive terms have distance 2.

A287805

Number of quinary sequences of length n such that no two consecutive terms have distance 2.

Terms

    a(0) =1a(1) =5a(2) =19a(3) =73a(4) =281a(5) =1083a(6) =4175a(7) =16097a(8) =62065a(9) =239307a(10) =922711a(11) =3557761a(12) =13717913a(13) =52893147a(14) =203943935a(15) =786361409a(16) =3032030689a(17) =11690820555a(18) =45077144455a(19) =173807214241a(20) =670161078089

External references