So I need a formula that calculates -1,-1,+1,+1,-1,-1,+1,+1,... for a value of n that is not a piece wise.(adsbygoogle = window.adsbygoogle || []).push({});

So far I have come up with (-1)^[2n/3] but I don't like using greatest integer

I also did:

[cos(n × ∏)]!

The notation is not setup correctly and anyone that knows how to do it proper let me know. It is supposed to function like this:

cos(n∏)cos((n-1)∏)cos((n-2)∏)cos((n-3)∏)... until cos((n-n)∏)

I have dug in algebraically but don't think there is a solution, anyone have any thoughts on this?

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# Need to figure out a formula that calculates -1,-1,+1,+1,-1,-1,+1,+1

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