Expansion of 1/((1-x)(1-2x)(1-4x)(1-5x)).

Terms

a(0) =1a(1) =12a(2) =95a(3) =630a(4) =3801a(5) =21672a(6) =119155a(7) =639210a(8) =3370301a(9) =17549532a(10) =90541815a(11) =463889790a(12) =2364180001a(13) =11999840592a(14) =60714998075a(15) =306438236370