# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a114287 Showing 1-1 of 1 %I A114287 #19 Feb 20 2024 02:32:03 %S A114287 0,512,4608,18432,38115,70883,134883,245475,402939,578555,840699, %T A114287 1213947,1725947,2257388,2938860,3823596,4948460,6208172,7613100, %U A114287 9341100,11294225,13391377,15851752,18367208,21353192,24865000,28961000 %N A114287 Sum of the cubes of the first n noncubefree numbers. %F A114287 a(n) = Sum_{k=1..n} A046099(k)^3. %F A114287 a(n) ~ c * n^4, where c = (zeta(3)/(zeta(3)-1))^3/4 = 52.6373493984... . - _Amiram Eldar_, Feb 20 2024 %e A114287 a(10) = 8^3 + 16^3 + 24^3 + 27^3 + 32^3 + 40^3 + 48^3 + 54^3 + 56^3 + 64^3 = 840699. %t A114287 noncubeFreeQ[n_] := Max[FactorInteger[n][[;; , 2]]] > 2; Join[{0}, Accumulate[Select[Range[200], noncubeFreeQ]^3]] (* _Amiram Eldar_, Feb 20 2024 *) %Y A114287 Cf. A046099, A114286. %K A114287 easy,nonn %O A114287 0,2 %A A114287 _Jonathan Vos Post_, Nov 20 2005 # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE