Number of 0..2 arrays of length n with no adjacent pair equal to its immediately preceding adjacent pair, and new values introduced in 0..2 order.

A212823

Number of 0..2 arrays of length n with no adjacent pair equal to its immediately preceding adjacent pair, and new values introduced in 0..2 order.

Terms

    a(0) =1a(1) =2a(2) =5a(3) =12a(4) =33a(5) =90a(6) =246a(7) =672a(8) =1836a(9) =5016a(10) =13704a(11) =37440a(12) =102288a(13) =279456a(14) =763488a(15) =2085888a(16) =5698752a(17) =15569280a(18) =42536064a(19) =116210688a(20) =317493504a(21) =867408384a(22) =2369803776a(23) =6474424320a(24) =17688456192a(25) =48325761024a(26) =132028434432a(27) =360708390912

External references