G.f. satisfies: A(x) = exp( Sum_{n>=1} x^n/n * Product_{d|n} A(d*x^n) ).

Terms

a(0) =1a(1) =1a(2) =2a(3) =4a(4) =10a(5) =22a(6) =59a(7) =140a(8) =375a(9) =948a(10) =2568a(11) =6670a(12) =18305a(13) =48755a(14) =134666a(15) =365881a(16) =1017559a(17) =2801369a(18) =7848220a(19) =21842497a(20) =61530519a(21) =172772037a(22) =489296057a(23) =1383418713a(24) =3936301710a(25) =11194022584a(26) =31983684187a(27) =91397174511a(28) =262107839548a(29) =752077861258