G.f. satisfies: A(x) = H(x*A(x)) where H(x) = A(x/H(x)) is the theta series of planar hexagonal lattice A_2 (A004016).

A200378

G.f. satisfies: A(x) = H(x*A(x)) where H(x) = A(x/H(x)) is the theta series of planar hexagonal lattice A_2 (A004016).

Terms

    a(0) =1a(1) =6a(2) =36a(3) =222a(4) =1446a(5) =10116a(6) =75924a(7) =602256a(8) =4958352a(9) =41783046a(10) =357442416a(11) =3091766904a(12) =26991194550a(13) =237605649780

External references