Number of -3..3 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.
A211721
Number of -3..3 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) =48a(1) =74a(2) =120a(3) =210a(4) =376a(5) =700a(6) =1312a(7) =2508a(8) =4800a(9) =9288a(10) =17968a(11) =35000a(12) =68144a(13) =133312a(14) =260688a(15) =511616a(16) =1003728a(17) =1974896a(18) =3884688a(19) =7659696a(20) =15100048a(21) =29828560a(22) =58914064a(23) =116565456a(24) =230605584a(25) =456911760a(26) =905224720a(27) =1795793552a(28) =3562275344
External references
- oeis: A211721