Partition numbers of the form 3*k.

Terms

a(0) =3a(1) =15a(2) =30a(3) =42a(4) =135a(5) =231a(6) =297a(7) =627a(8) =792a(9) =1002a(10) =1575a(11) =2436a(12) =5604a(13) =8349a(14) =10143a(15) =14883a(16) =31185a(17) =37338a(18) =44583a(19) =63261a(20) =105558a(21) =147273a(22) =239943a(23) =281589a(24) =329931a(25) =614154a(26) =1121505a(27) =1505499a(28) =3087735a(29) =4087968