# Get Triggy With It!

**Geometry**Level 5

\[\large z = \left| \sum _{ k=1 }^{ 2015 }{ \sum _{ n=1 }^{ k }{ \cos { \left( \frac { 2\pi n }{ 2k+1 } \right) } } } \right| \]

Evaluate \(\left\lfloor z \right\rfloor \).

\[\large z = \left| \sum _{ k=1 }^{ 2015 }{ \sum _{ n=1 }^{ k }{ \cos { \left( \frac { 2\pi n }{ 2k+1 } \right) } } } \right| \]

Evaluate \(\left\lfloor z \right\rfloor \).

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