Number of horizontally convex n-ominoes in which the top row has at least 2 squares and the rightmost square in the top row is above the leftmost square in the second row.
A049220
Number of horizontally convex n-ominoes in which the top row has at least 2 squares and the rightmost square in the top row is above the leftmost square in the second row.
Terms
- a(0) =0a(1) =0a(2) =1a(3) =3a(4) =9a(5) =28a(6) =89a(7) =285a(8) =914a(9) =2931a(10) =9397a(11) =30124a(12) =96565a(13) =309545a(14) =992266a(15) =3180775a(16) =10196193a(17) =32684604a(18) =104772769a(19) =335856389a(20) =1076610978a(21) =3451151243a(22) =11062904925a(23) =35462909836a(24) =113678819677a(25) =364405349233
External references
- oeis: A049220