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A183143
[1/r]+[2/r]+...+[n/r], where r=sqrt(3) and []=floor.
4
0, 1, 2, 4, 6, 9, 13, 17, 22, 27, 33, 39, 46, 54, 62, 71, 80, 90, 100, 111, 123, 135, 148, 161, 175, 190, 205, 221, 237, 254, 271, 289, 308, 327, 347, 367, 388, 409, 431, 454, 477, 501, 525, 550, 575, 601, 628, 655, 683, 711, 740, 770, 800, 831
OFFSET
1,3
COMMENTS
A183143 + A183144 = A000217 (the triangular numbers).
FORMULA
[1/r]+[2/r]+...+[n/r], where r=sqrt(3) and []=floor.
MATHEMATICA
Accumulate[Floor[Range[60]/Sqrt[3]]] (* Harvey P. Dale, Sep 10 2019 *)
PROG
(PARI) default(realprecision, 100); r=sqrt(3); for(n=1, 99, print1(sum(k=1, n, floor(k/r)), ", "))
CROSSREFS
KEYWORD
nonn
AUTHOR
Clark Kimberling, Dec 26 2010
STATUS
approved