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# help

0
87
4

Find all f(k) such that $$\sum_{k=1}^n f(k) = n^3.$$

Feb 10, 2020

#1
0

From the formulas 1 + 2 + .. + n = n(n + 1)/2 and 1^2 + 2^2 + ... + n^2 = n(n + 1)(2n + 1)/6, it follows that f(k) = k^4/4 + k^3/2 + k^2/4.

Feb 10, 2020
#2
0

Thank you!

Feb 10, 2020
#3
+29200
+5

I get the following:

Feb 10, 2020
#4
+24344
+2

Find  $$f(k)$$ such that $$\sum \limits_{k=1}^n f(k) = n^3$$.

Feb 10, 2020