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A014811
a(n) = Sum_{k=1..n-1} ceiling(k^2/n).
2
0, 1, 3, 5, 8, 12, 17, 22, 26, 33, 41, 49, 56, 66, 77, 86, 96, 107, 121, 135, 148, 162, 179, 196, 206, 225, 243, 263, 280, 302, 323, 344, 364, 385, 411, 433, 456, 482, 511, 538, 560, 589, 617, 649, 676, 708, 741, 774, 798, 831, 869, 903, 936, 972, 1013, 1052
OFFSET
1,3
REFERENCES
M. Eichler and D. Zagier, The Theory of Jacobi Forms, Birkhauser, 1985, p. 103.
MAPLE
f := n->sum( ceil(k^2/n), k=1..n-1);
PROG
(PARI) a(n)=sum(k=1, n-1, ceil(k^2/n))
CROSSREFS
Sequence in context: A255981 A020678 A310034 * A282513 A241567 A131674
KEYWORD
nonn
STATUS
approved