Number of partitions of n into parts 3k or 3k+1.

Terms

a(0) =1a(1) =1a(2) =1a(3) =2a(4) =3a(5) =3a(6) =5a(7) =7a(8) =8a(9) =11a(10) =15a(11) =17a(12) =23a(13) =30a(14) =35a(15) =44a(16) =57a(17) =66a(18) =82a(19) =103a(20) =121a(21) =146a(22) =181a(23) =211a(24) =253a(25) =308a(26) =360a(27) =425a(28) =513a(29) =596