Number of 0..1 arrays x(0..n-1) of n elements with zero n-1st difference.

Terms

a(0) =1a(1) =2a(2) =2a(3) =4a(4) =2a(5) =8a(6) =2a(7) =16a(8) =6a(9) =32a(10) =2a(11) =64a(12) =2a(13) =144a(14) =14a(15) =256a(16) =2a(17) =512a(18) =2a(19) =1024a(20) =6a(21) =2048a(22) =2a(23) =4096a(24) =50a(25) =8192a(26) =6a(27) =16384a(28) =2a(29) =34816