+0

closed form sum

0
116
3

Find the closed form sum of 1*2*3 + 2*3*4 + 3*4*5 + ... + n(n + 1)(n + 2).

Nov 27, 2020

#1
+9185
0

$$\sum\limits_{k=1}^{n}(k)(k+1)(k+2)$$ .

.
Nov 27, 2020
#2
0

The "closed form" of the sequence is:

a_n = n^3 + 3 n^2 + 2 n

Nov 27, 2020
#3
+31703
+2

Not exactly a derivation, but

It can be proved by induction.

Nov 28, 2020
edited by Alan  Nov 28, 2020