Number of distinct partitions of triangular numbers n*(n+1)/2 into 3 parts for n>=1.

Terms

a(0) =0a(1) =0a(2) =1a(3) =4a(4) =12a(5) =27a(6) =52a(7) =91a(8) =147a(9) =225a(10) =331a(11) =469a(12) =645a(13) =867a(14) =1141a(15) =1474a(16) =1875a(17) =2352a(18) =2914a(19) =3571a(20) =4332a(21) =5208a(22) =6211a(23) =7351a(24) =8640a(25) =10092a(26) =11719a(27) =13534a(28) =15552a(29) =17787