Number of 3 X 3 X 3 triangular 0..n arrays with some element less than a w, nw or ne neighbor exactly once.
A271035
Number of 3 X 3 X 3 triangular 0..n arrays with some element less than a w, nw or ne neighbor exactly once.
Terms
- a(0) =10a(1) =72a(2) =294a(3) =896a(4) =2268a(5) =5040a(6) =10164a(7) =19008a(8) =33462a(9) =56056a(10) =90090a(11) =139776a(12) =210392a(13) =308448a(14) =441864a(15) =620160a(16) =854658a(17) =1158696a(18) =1547854a(19) =2040192a(20) =2656500a(21) =3420560a(22) =4359420a(23) =5503680a(24) =6887790a(25) =8550360a(26) =10534482a(27) =12888064a(28) =15664176a(29) =18921408
External references
- oeis: A271035