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A132296
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Sum of the noncube numbers less than or equal to n.
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1
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0, 2, 5, 9, 14, 20, 27, 27, 36, 46, 57, 69, 82, 96, 111, 127, 144, 162, 181, 201, 222, 244, 267, 291, 316, 342, 342, 370, 399, 429, 460, 492, 525, 559, 594, 630, 667, 705, 744, 784, 825, 867, 910, 954, 999, 1045, 1092, 1140, 1189, 1239, 1290, 1342, 1395, 1449
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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FORMULA
| Let r = floor(n^(1/3)). Then a(n) = n(n+1)/2 - (r(r+1)/2)^2.
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EXAMPLE
| Let n=10.
The sum of the noncube numbers <= 10 is 2+3+4+5+6+7+9+10 = 46, the 10-th entry in the sequence.
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PROG
| (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", "))
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CROSSREFS
| Sequence in context: A024201 A110443 A130029 * A112265 A075543 A132315
Adjacent sequences: A132293 A132294 A132295 * A132297 A132298 A132299
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KEYWORD
| nonn
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AUTHOR
| Cino Hilliard (hillcino368(AT)hotmail.com), Nov 07 2007
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