What is the sum of $1^4 + 2^4 + 3^4+ \dots + n^4$ and the derivation for that expression What is the sum of $1^4 + 2^4 + 3^4+ \dots + n^4$ and the derivation for that expression using sums $\sum$ and double sums $\sum$$\sum$?

Solution to the question can be find on my YouTube Channel " Cipher". Following is the link.
https://youtu.be/_y_Q8-3g-M8 
