Number of zero-sum -2..2 arrays of n elements with adjacent element differences also in -2..2.

A202246

Number of zero-sum -2..2 arrays of n elements with adjacent element differences also in -2..2.

Terms

    a(0) =1a(1) =3a(2) =9a(3) =31a(4) =107a(5) =387a(6) =1415a(7) =5231a(8) =19477a(9) =72933a(10) =274339a(11) =1035807a(12) =3923229a(13) =14900005a(14) =56721943a(15) =216377047a(16) =826917803a(17) =3165318823a(18) =12133973901a(19) =46575395693a(20) =178988128029a(21) =688588254425

External references