Partial sums of ceiling(n^2/7).

Terms

a(0) =0a(1) =1a(2) =2a(3) =4a(4) =7a(5) =11a(6) =17a(7) =24a(8) =34a(9) =46a(10) =61a(11) =79a(12) =100a(13) =125a(14) =153a(15) =186a(16) =223a(17) =265a(18) =312a(19) =364a(20) =422a(21) =485a(22) =555a(23) =631a(24) =714a(25) =804a(26) =901a(27) =1006a(28) =1118a(29) =1239