

A077113


Number of integer cubes <= n^2.


3



1, 2, 2, 3, 3, 3, 4, 4, 5, 5, 5, 5, 6, 6, 6, 7, 7, 7, 7, 8, 8, 8, 8, 9, 9, 9, 9, 10, 10, 10, 10, 10, 11, 11, 11, 11, 11, 12, 12, 12, 12, 12, 13, 13, 13, 13, 13, 14, 14, 14, 14, 14, 14, 15, 15, 15, 15, 15, 15, 16, 16, 16, 16, 16, 17, 17, 17, 17, 17, 17, 17, 18, 18, 18, 18, 18, 18, 19
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OFFSET

0,2


COMMENTS

a(n) is the least number m such that m^3 > n^2.  Zak Seidov, May 03 2005


LINKS

Table of n, a(n) for n=0..77.


FORMULA

a(n) = floor(n^(2/3))+1.
a(n) = [x^(n^2)] (1/(1  x))*Sum_{k>=0} x^(k^3).  Ilya Gutkovskiy, Apr 20 2018


EXAMPLE

Cubes <= 10^2: 0, 1, 8, 27 and 64, hence a(10)=5;


MATHEMATICA

Table[Floor[n^(2/3) + 1], {n, 0, 100}] (* Zak Seidov, May 03 2005 *)


CROSSREFS

Cf. A077106, A026409, A026414, A054071, A077121.
Sequence in context: A273263 A274533 A163127 * A143796 A245473 A306904
Adjacent sequences: A077110 A077111 A077112 * A077114 A077115 A077116


KEYWORD

nonn


AUTHOR

Reinhard Zumkeller, Oct 29 2002


EXTENSIONS

Edited by N. J. A. Sloane, Aug 29 2008 at the suggestion of R. J. Mathar


STATUS

approved



