Number of -2..2 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 one, three or four distinct values for every i<=n and j<=n.
A211464
Number of -2..2 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 one, three or four distinct values for every i<=n and j<=n.
Terms
- a(0) =21a(1) =89a(2) =353a(3) =1373a(4) =5225a(5) =19645a(6) =73105a(7) =270125a(8) =992545a(9) =3631741a(10) =13245457a(11) =48187085a(12) =174966209a(13) =634348221a(14) =2297224145a(15) =8311862669a(16) =30054358337a(17) =108618731197a(18) =392419038993
External references
- oeis: A211464