Number of -2..2 arrays x(i) of n+1 elements i=1..n+1 with set{t,u,v in 0,1}((x[i+t]+x[j+u]+x[k+v])*(-1)^(t+u+v)) having two or four distinct values for every i,j,k<=n.
A211567
Number of -2..2 arrays x(i) of n+1 elements i=1..n+1 with set{t,u,v in 0,1}((x[i+t]+x[j+u]+x[k+v])*(-1)^(t+u+v)) having two or four distinct values for every i,j,k<=n.
Terms
- a(0) =24a(1) =40a(2) =68a(3) =122a(4) =220a(5) =410a(6) =764a(7) =1454a(8) =2764a(9) =5330a(10) =10268a(11) =19982a(12) =38860a(13) =76130a(14) =149084a(15) =293534a(16) =577804a(17) =1141970a(18) =2256668a(19) =4472942a(20) =8865100a(21) =17610050a(22) =34979804a(23) =69601214a(24) =138485644a(25) =275900210a(26) =549658268a(27) =1096111502a(28) =2185812940a(29) =4362027170
External references
- oeis: A211567