Number of n X 3 0..2 arrays with horizontal differences mod 3 never 1, vertical differences mod 3 never -1, rows lexicographically nondecreasing, and columns lexicographically nonincreasing.
A229423
Number of n X 3 0..2 arrays with horizontal differences mod 3 never 1, vertical differences mod 3 never -1, rows lexicographically nondecreasing, and columns lexicographically nonincreasing.
Terms
- a(0) =8a(1) =27a(2) =83a(3) =222a(4) =524a(5) =1116a(6) =2187a(7) =4005a(8) =6936a(9) =11465a(10) =18219a(11) =27992a(12) =41772a(13) =60770a(14) =86451a(15) =120567a(16) =165192a(17) =222759a(18) =296099a(19) =388482a(20) =503660a(21) =645912a(22) =820091a(23) =1031673a(24) =1286808a(25) =1592373a(26) =1956027a(27) =2386268a(28) =2892492a(29) =3485054
External references
- oeis: A229423