Partial sums of A140091.

Terms

a(0) =0a(1) =6a(2) =21a(3) =48a(4) =90a(5) =150a(6) =231a(7) =336a(8) =468a(9) =630a(10) =825a(11) =1056a(12) =1326a(13) =1638a(14) =1995a(15) =2400a(16) =2856a(17) =3366a(18) =3933a(19) =4560a(20) =5250a(21) =6006a(22) =6831a(23) =7728a(24) =8700a(25) =9750a(26) =10881a(27) =12096a(28) =13398a(29) =14790