a(n) = Pell(n)*A008653(n) for n>=1, with a(0)=1, where A008653 is the theta series of direct sum of 2 copies of hexagonal lattice.

A209447

a(n) = Pell(n)*A008653(n) for n>=1, with a(0)=1, where A008653 is the theta series of direct sum of 2 copies of hexagonal lattice.

Terms

    a(0) =1a(1) =12a(2) =72a(3) =60a(4) =1008a(5) =2088a(6) =2520a(7) =16224a(8) =73440a(9) =11820a(10) =513648a(11) =826704a(12) =1164240a(13) =5621448a(14) =23265216a(15) =14041800a(16) =175149504a(17) =245524824a(18) =98791560a(19) =1590026160a(20) =8061191712a(21) =3706940640a(22) =40272058656a(23) =64816900128a(24) =97801149600a(25) =487966581012a(27) =91744440540

External references