Number of length n+2 0..3 arrays with no three consecutive terms having the sum of any two elements equal to twice the third.

A248456

Number of length n+2 0..3 arrays with no three consecutive terms having the sum of any two elements equal to twice the third.

Terms

    a(0) =48a(1) =148a(2) =460a(3) =1436a(4) =4488a(5) =14040a(6) =43940a(7) =137532a(8) =430508a(9) =1347652a(10) =4218704a(11) =13206360a(12) =41341772a(13) =129418260a(14) =405137308a(15) =1268262348a(16) =3970233208a(17) =12428621208a(18) =38907193300a(19) =121797075276a(20) =381279818252

External references