Partial sums of A028357.

Terms

a(0) =1a(1) =4a(2) =10a(3) =20a(4) =33a(5) =48a(6) =64a(7) =82a(8) =103a(9) =128a(10) =156a(11) =186a(12) =217a(13) =250a(14) =286a(15) =326a(16) =369a(17) =414a(18) =460a(19) =508a(20) =559a(21) =614a(22) =672a(23) =732a(24) =793a(25) =856a(26) =922a(27) =992a(28) =1065a(29) =1140