Number of nonnegative integer arrays of length n summing to n without adjacent equal values.

Terms

a(0) =1a(1) =1a(2) =2a(3) =7a(4) =14a(5) =30a(6) =76a(7) =188a(8) =444a(9) =1075a(10) =2656a(11) =6504a(12) =15926a(13) =39316a(14) =97252a(15) =240597a(16) =596686a(17) =1482971a(18) =3689768a(19) =9191590a(20) =22927718a(21) =57253334a(22) =143101896a(23) =358003469a(24) =896391914a(25) =2246149936a(26) =5632310800a(27) =14132640565a(28) =35483595966a(29) =89141668532