Defined by Product 1/(1-x^k)^a_k, k=1..infinity = 1+x+2*Sum(a_k*x^k, k=2..infinity).

A056198

Defined by Product 1/(1-x^k)^a_k, k=1..infinity = 1+x+2*Sum(a_k*x^k, k=2..infinity).

Terms

    a(0) =1a(1) =2a(2) =3a(3) =9a(4) =24a(5) =76a(6) =236a(7) =785a(8) =2634a(9) =9106a(10) =31870a(11) =113371a(12) =407438a(13) =1479526a(14) =5415700a(15) =19970119a(16) =74096864a(17) =276466199a(18) =1036598162a(19) =3903844089a(20) =14760093096a(21) =56006631629a(22) =213206289068a(23) =814045174247

External references