Number of 2 X n 0..2 arrays with some element plus some horizontally, diagonally or antidiagonally adjacent neighbor totalling two not more than once.
A269053
Number of 2 X n 0..2 arrays with some element plus some horizontally, diagonally or antidiagonally adjacent neighbor totalling two not more than once.
Terms
- a(0) =9a(1) =42a(2) =102a(3) =360a(4) =1068a(5) =3288a(6) =9864a(7) =29472a(8) =87312a(9) =257184a(10) =753504a(11) =2197632a(12) =6383808a(13) =18478464a(14) =53318784a(15) =153414144a(16) =440293632a(17) =1260710400a(18) =3602253312a(19) =10273007616a(20) =29245172736a(21) =83119822848a(22) =235886217216a(23) =668491456512
External references
- oeis: A269053