Sizes of successive clusters in hexagonal lattice A_2 centered at deep hole.

Terms

a(0) =3a(1) =6a(2) =12a(3) =12a(4) =18a(5) =21a(6) =27a(7) =27a(8) =30a(9) =36a(10) =42a(11) =42a(12) =48a(13) =48a(14) =54a(15) =54a(16) =63a(17) =69a(18) =69a(19) =69a(20) =75a(21) =78a(22) =84a(23) =84a(24) =90a(25) =96a(26) =102a(27) =102a(28) =102a(29) =102