Number of polyominoes consisting of 9 regular unit n-gons.

Terms

a(0) =160a(1) =1285a(2) =14445a(3) =6572a(4) =14982a(5) =65323a(6) =280014a(7) =664411a(8) =1908239a(9) =1314914a(10) =1968684a(11) =4158216a(12) =9707046a(13) =17054708a(14) =33522023a(15) =26019735a(16) =33942901a(17) =56537856a(18) =100952307a(19) =153177526a(20) =251530341a(21) =208524646a(22) =254079408a(23) =374310135a(24) =586169115a(25) =812395658