Number of triangular partitions of n of order 3.

Terms

a(0) =1a(1) =3a(2) =6a(3) =12a(4) =21a(5) =34a(6) =54a(7) =81a(8) =117a(9) =166a(10) =229a(11) =309a(12) =411a(13) =537a(14) =691a(15) =880a(16) =1107a(17) =1377a(18) =1699a(19) =2077a(20) =2518a(21) =3033a(22) =3627a(23) =4309a(24) =5092a(25) =5983a(26) =6993a(27) =8137a(28) =9424a(29) =10867