Number of nX3 0..1 arrays with every element unequal to 0, 1, 2, 4 or 5 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.
A320404
Number of nX3 0..1 arrays with every element unequal to 0, 1, 2, 4 or 5 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.
Terms
- a(0) =4a(1) =14a(2) =47a(3) =156a(4) =548a(5) =1970a(6) =7049a(7) =25364a(8) =91307a(9) =328700a(10) =1183518a(11) =4261468a(12) =15344635a(13) =55253618a(14) =198959548a(15) =716424463a(16) =2579743890a(17) =9289300111a(18) =33449490192a(19) =120447025154a(20) =433713239426
External references
- oeis: A320404