Number of words of length n over the alphabet {1,2,3,4,5} such that 1 is not followed by an odd letter.

A123347

Number of words of length n over the alphabet {1,2,3,4,5} such that 1 is not followed by an odd letter.

Terms

    a(0) =1a(1) =5a(2) =22a(3) =98a(4) =436a(5) =1940a(6) =8632a(7) =38408a(8) =170896a(9) =760400a(10) =3383392a(11) =15054368a(12) =66984256a(13) =298045760a(14) =1326151552a(15) =5900697728a(16) =26255094016a(17) =116821771520a(18) =519797274112

External references