La [tex]f(n)[/tex] være heltallet nærmest [tex]\sqrt[4]{n}[/tex].
Finn [tex]\sum^{2011}_{k=1} \frac{1}{f(k)}[/tex].
Sum
Moderators: Vektormannen, espen180, Aleks855, Solar Plexsus, Gustav, Nebuchadnezzar, Janhaa
[tex]1.5^4=5.0625[/tex]
[tex]2.5^4=39.0625[/tex]
[tex]3.5^4=150.0625[/tex]
[tex]4.5^4=410.0625[/tex]
[tex]5.5^4=915.0625[/tex]
[tex]6.5^4=1785.0625[/tex]
[tex]7.5^4=3164.0625[/tex]
[tex]\sum_{k=1}^{2011} \frac{1}{f(k)}=5+\frac{34}{2}+\frac{111}{3}+\frac{260}{4}+\frac{505}{5}+\frac{870}{6}+\frac{226}{7}=402+\frac{2}{7}[/tex]
[tex]2.5^4=39.0625[/tex]
[tex]3.5^4=150.0625[/tex]
[tex]4.5^4=410.0625[/tex]
[tex]5.5^4=915.0625[/tex]
[tex]6.5^4=1785.0625[/tex]
[tex]7.5^4=3164.0625[/tex]
[tex]\sum_{k=1}^{2011} \frac{1}{f(k)}=5+\frac{34}{2}+\frac{111}{3}+\frac{260}{4}+\frac{505}{5}+\frac{870}{6}+\frac{226}{7}=402+\frac{2}{7}[/tex]