Number of nX1 0..4 arrays with every element value z a city block distance of exactly z from another element value z.

A209717

Number of nX1 0..4 arrays with every element value z a city block distance of exactly z from another element value z.

Terms

    a(0) =1a(1) =2a(2) =5a(3) =12a(4) =33a(5) =87a(6) =227a(7) =583a(8) =1538a(9) =4067a(10) =10633a(11) =27837a(12) =72387a(13) =188811a(14) =493437a(15) =1288622a(16) =3355810a(17) =8740288a(18) =22783725a(19) =59403150a(20) =154824944a(21) =403509362a(22) =1051651919a(23) =2740858097a(24) =7144656505a(25) =18623531350a(26) =48542955448a(27) =126526434447

External references