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Would a summation of floor[cos^2π(((j-1)!+1)/j)] from j=1 to x be the same as π(x)?

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I cannot read the formula, sorry. The first $\pi$ is the number Pi ? – Dietrich Burde Jun 12 '13 at 18:29
It's probably off by 1. But why do you ask? – Steven Landsburg Jun 12 '13 at 18:34
Do you mean I should not ask what the formula is ? Is $\pi ((j-1)!+1)$ the prime counting function, or $(j-1)!+1$ times $\pi$ ? – Dietrich Burde Jun 12 '13 at 18:43
This looks like Wilson's Theorem in disguise. – Barry Cipra Jun 12 '13 at 18:43
@Dietrich, I think Steven's comment and question was directed to the OP, not to you. – Barry Cipra Jun 12 '13 at 18:45

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