T(n,k)=1/7 the number of nXk 0..6 arrays with every element equal to exactly one or two of its horizontal and vertical neighbors.
A185409
T(n,k)=1/7 the number of nXk 0..6 arrays with every element equal to exactly one or two of its horizontal and vertical neighbors.
Terms
- a(0) =0a(1) =1a(2) =1a(3) =1a(4) =13a(5) =1a(6) =7a(7) =150a(8) =150a(9) =7a(10) =13a(11) =1848a(12) =5040a(13) =1848a(14) =13a(15) =55a(16) =22656a(17) =279918a(18) =279918a(19) =22656a(20) =55a(21) =133a(22) =278832a(23) =12205368a(24) =53808534a(25) =12205368a(26) =278832a(27) =133a(28) =463a(29) =3430776
External references
- oeis: A185409