p-INVERT of the positive integers, where p(S) = (1 - S^2)^3.

Terms

a(0) =0a(1) =3a(2) =12a(3) =36a(4) =108a(5) =331a(6) =1008a(7) =3027a(8) =8992a(9) =26502a(10) =77592a(11) =225806a(12) =653544a(13) =1882224a(14) =5396776a(15) =15411399a(16) =43847688a(17) =124331457a(18) =351448620a(19) =990586686a(20) =2784612380a(21) =7808372811a(22) =21845061504a(23) =60983031772a(24) =169897677504a(25) =472435652577