Number of n-celled polyominoes with exactly 5 holes.

Terms

a(0) =0a(1) =0a(2) =0a(3) =0a(4) =0a(5) =0a(6) =0a(7) =0a(8) =0a(9) =0a(10) =0a(11) =0a(12) =0a(13) =0a(14) =0a(15) =0a(16) =0a(17) =0a(18) =1a(19) =21a(20) =573a(21) =9140a(22) =105417a(23) =982767a(24) =7919375a(25) =57387444a(26) =383757344a(27) =2410292366