Hilltop maps: number of n X 2 binary arrays indicating the locations of corresponding elements not exceeded by any horizontal or antidiagonal neighbor in a random 0..1 n X 2 array.
A221440
Hilltop maps: number of n X 2 binary arrays indicating the locations of corresponding elements not exceeded by any horizontal or antidiagonal neighbor in a random 0..1 n X 2 array.
Terms
- a(0) =3a(1) =9a(2) =31a(3) =105a(4) =355a(5) =1201a(6) =4063a(7) =13745a(8) =46499a(9) =157305a(10) =532159a(11) =1800281a(12) =6090307a(13) =20603361a(14) =69700671a(15) =235795681a(16) =797691075a(17) =2698569577a(18) =9129195487a(19) =30883847113a(20) =104479306403a(21) =353450961809
External references
- oeis: A221440