a(n) = Sum_{k=1..n} nearest integer to n/k (if n/k is midway between two numbers take the smaller).

Terms

a(0) =1a(1) =3a(2) =5a(3) =8a(4) =11a(5) =14a(6) =17a(7) =22a(8) =24a(9) =28a(10) =33a(11) =36a(12) =40a(13) =45a(14) =48a(15) =53a(16) =57a(17) =62a(18) =66a(19) =71a(20) =74a(21) =79a(22) =86a(23) =89a(24) =93a(25) =99a(26) =102a(27) =109a(28) =114a(29) =117