Site percolation series for square lattice.

Terms

a(0) =1a(1) =2a(2) =4a(3) =7a(4) =12a(5) =20a(6) =33a(7) =53a(8) =85a(9) =133a(10) =210a(11) =322a(12) =505a(13) =759a(14) =1192a(15) =1748a(16) =2782a(17) =3931a(18) =6476a(19) =8579a(20) =15216a(21) =17847a(22) =36761a(23) =33612a(24) =93961a(25) =47282a(26) =262987a(27) =-16105a(28) =827382a(29) =-571524