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

A287817

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

Terms

    a(0) =1a(1) =9a(2) =67a(3) =501a(4) =3747a(5) =28025a(6) =209609a(7) =1567743a(8) =11725731a(9) =87701095a(10) =655949055a(11) =4906086571a(12) =36694443381a(13) =274451368893

External references