G.f. satisfies A(x) = exp( 3 * Sum_{k>=1} A(-x^k) * x^k/k ).

Terms

a(0) =1a(1) =3a(2) =-3a(3) =-26a(4) =48a(5) =444a(6) =-920a(7) =-9126a(8) =19587a(9) =204214a(10) =-449496a(11) =-4841001a(12) =10856283a(13) =119585034a(14) =-271813440a(15) =-3044796399a(16) =6991433415a(17) =79341313335a(18) =-183641493481