Number of n X 3 0..2 arrays with rows and columns lexicographically nondecreasing read forwards and nonincreasing read backwards.

A201695

Number of n X 3 0..2 arrays with rows and columns lexicographically nondecreasing read forwards and nonincreasing read backwards.

Terms

    a(0) =3a(1) =18a(2) =116a(3) =395a(4) =989a(5) =2068a(6) =3838a(7) =6541a(8) =10455a(9) =15894a(10) =23208a(11) =32783a(12) =45041a(13) =60440a(14) =79474a(15) =102673a(16) =130603a(17) =163866a(18) =203100a(19) =248979a(20) =302213a(21) =363548a(22) =433766a(23) =513685a(24) =604159a(25) =706078a(26) =820368a(27) =947991a(28) =1089945a(29) =1247264

External references