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 A174059 a(n) = ceiling(Sum_{k=1..n} sqrt(k)). 1
 0, 1, 3, 5, 7, 9, 11, 14, 17, 20, 23, 26, 30, 33, 37, 41, 45, 49, 53, 58, 62, 67, 71, 76, 81, 86, 91, 96, 102, 107, 113, 118, 124, 130, 135, 141, 147, 153, 160, 166, 172, 179, 185, 192, 198, 205, 212, 219, 225, 232, 240, 247, 254, 261, 269, 276, 283, 291, 299, 306 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 LINKS Robert Israel, Table of n, a(n) for n = 0..1000 FORMULA a(n) = 2/3*n^(3/2) + 1/2*n^(1/2) + O(1).  It appears that the absolute value of the difference is always less than 1. - Robert Israel, May 06 2019 MAPLE map(ceil, ListTools:-PartialSums([seq((sqrt(k)), k=0..100)])); # Robert Israel, May 06 2019 MATHEMATICA s=0; lst={}; Do[s+=Sqrt[n]; AppendTo[lst, Ceiling[s]], {n, 0, 6!}]; lst Ceiling[Accumulate[Sqrt[Range[0, 60]]]] (* Harvey P. Dale, Aug 29 2016 *) CROSSREFS Cf. A025224, A174058 Sequence in context: A175269 A318919 A279539 * A321676 A268292 A240992 Adjacent sequences:  A174056 A174057 A174058 * A174060 A174061 A174062 KEYWORD nonn AUTHOR Vladimir Joseph Stephan Orlovsky, Mar 06 2010 EXTENSIONS Offset corrected by Robert Israel, May 06 2019 STATUS approved

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Last modified May 13 13:49 EDT 2021. Contains 343857 sequences. (Running on oeis4.)