%I #16 Sep 04 2024 08:47:02
%S 0,2,5,9,14,20,27,27,36,46,57,69,82,96,111,127,144,162,181,201,222,
%T 244,267,291,316,342,342,370,399,429,460,492,525,559,594,630,667,705,
%U 744,784,825,867,910,954,999,1045,1092,1140,1189,1239,1290,1342,1395,1449
%N Sum of the noncube numbers less than or equal to n.
%H Harvey P. Dale, <a href="/A132296/b132296.txt">Table of n, a(n) for n = 1..1000</a>
%F Let r = floor(n^(1/3)) = A048766(n). Then a(n) = n(n+1)/2 - (r(r+1)/2)^2 = A000217(n)-A000537(r).
%e Let n=10. The sum of the noncube numbers <= 10 is 2+3+4+5+6+7+9+10 = 46, the 10th entry in the sequence.
%t Accumulate[Table[If[IntegerQ[n^(1/3)],0,n],{n,60}]] (* _Harvey P. Dale_, Oct 16 2012 *)
%o (PARI) g(n)=for(x=1,n,r=floor(x^(1/3));sumcu=(r*(r+1)/2)^2;sn=x*(x+1)/2;print1(sn-sumcu","))
%o (Python)
%o from sympy import integer_nthroot
%o def A132296(n): return n*(n+1)-(((r:=integer_nthroot(n,3)[0])*(r+1))**2>>1)>>1 # _Chai Wah Wu_, Sep 03 2024
%K nonn
%O 1,2
%A _Cino Hilliard_, Nov 07 2007