Number of n X 2 1..4 arrays containing at least one of each value, all equal values connected, rows considered as a single number in nondecreasing order, and columns considered as a single number in nonincreasing order.

A166826

Number of n X 2 1..4 arrays containing at least one of each value, all equal values connected, rows considered as a single number in nondecreasing order, and columns considered as a single number in nonincreasing order.

Terms

    a(0) =0a(1) =4a(2) =49a(3) =219a(4) =666a(5) =1636a(6) =3499a(7) =6783a(8) =12212a(9) =20748a(10) =33637a(11) =52459a(12) =79182a(13) =116220a(14) =166495a(15) =233503a(16) =321384a(17) =434996a(18) =579993a(19) =762907a(20) =991234a(21) =1273524a(22) =1619475a(23) =2040031a(24) =2547484a(25) =3155580a(26) =3879629a(27) =4736619a(28) =5745334a(29) =6926476

External references