Partial sums of A005557.

Terms

a(0) =42a(1) =174a(2) =471a(3) =1043a(4) =2044a(5) =3682a(6) =6230a(7) =10038a(8) =15546a(9) =23298a(10) =33957a(11) =48321a(12) =67340a(13) =92134a(14) =124012a(15) =164492a(16) =215322a(17) =278502a(18) =356307a(19) =451311a(20) =566412a(21) =704858a(22) =870274a(23) =1066690a(24) =1298570a(25) =1570842a(26) =1888929a(27) =2258781a(28) =2686908a(29) =3180414