Number of -4..4 arrays x(i) of n+1 elements i=1..n+1 with x(i)+x(j), x(i+1)+x(j+1), -(x(i)+x(j+1)), and -(x(i+1)+x(j)) having three or four distinct values for every i<=n and j<=n.
A211691
Number of -4..4 arrays x(i) of n+1 elements i=1..n+1 with x(i)+x(j), x(i+1)+x(j+1), -(x(i)+x(j+1)), and -(x(i+1)+x(j)) having three or four distinct values for every i<=n and j<=n.
Terms
- a(0) =68a(1) =516a(2) =3848a(3) =28464a(4) =208560a(5) =1516160a(6) =10941536a(7) =78444752a(8) =559061552a(9) =3962850688a(10) =27952463280a(11) =196285510848
External references
- oeis: A211691