Number of n-length words on {0,1,2,3} in which 0 appears only in runs of length 2.

A255116

Number of n-length words on {0,1,2,3} in which 0 appears only in runs of length 2.

Terms

    a(0) =1a(1) =3a(2) =10a(3) =33a(4) =108a(5) =354a(6) =1161a(7) =3807a(8) =12483a(9) =40932a(10) =134217a(11) =440100a(12) =1443096a(13) =4731939a(14) =15516117a(15) =50877639a(16) =166828734a(17) =547034553a(18) =1793736576a(19) =5881695930a(20) =19286191449a(21) =63239784075a(22) =207364440015a(23) =679951894392

External references