Timeline for How to evaluate this sum of roots of unity with condition to zero
Current License: CC BY-SA 3.0
3 events
| when toggle format | what | by | license | comment | |
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| Sep 18, 2017 at 18:36 | comment | added | Andrew | The last equality in (2) is obtained by first evaluating the geometric series with n varying from 1 to N-k, and then evaluating the geometric series with k varying from 1 to N-1. The result of each step can be simplified by eliminating terms containing $exp(i*\pi*(s_1+s_2))$. | |
| Sep 18, 2017 at 18:26 | comment | added | Fedor Petrov | I do not understand the last equality in (2) | |
| Sep 18, 2017 at 16:17 | history | asked | Andrew | CC BY-SA 3.0 |