\(1\times2+2\times5+3\times8+4\times11+...+n(3n-1)=?\)
This app is also available in stereo:
\(1\times2+2\times5+3\times8+4\times11+...+n(3n-1)=?\)
This app is also available in stereo:
Created on: 2007
Last update: 2024-12-05 16:14:19+0000
This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.
