How can I calculate the frecuency of this circuit?
In the circuit you've shown there will be no frequency;  there'll only be a single output pulse, as shown below.

Here's how it works: 

When the circuit powers up, C1 will start out discharged, which will pull TRIG  low, force OUT high, and make DIS go open collector. 

C1 will then start charging toward Vcc through R1 and R2, and when THRS detects that the voltage across C1  has risen to 2/3 Vcc, OUT will go low and DIS will be connected to ground through a low impedance.

C1 will now start discharging through R2 and R3, and when it gets to 1/3 Vcc the plan is that TRIG will detect that voltage then force OUT high, starting the cycle anew.

The problem with this circuit is that when DIS is ON and discharging C1,  R1 and R3 form a voltage divider which keeps C1 from ever  falling below Vcc/2, the consequence being that TRIG will never see Vcc/3 and, after the first pulse, OUT will remain low forever. 

I've shown the 1/3 and 2/3 Vcc points on the green trace, showing how 1/3 Vcc can never be reached after the initial pulse.

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