How do i find the value of p for this integration?

Dell
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using the integral, find the values of "p" so that the series converges

\sum1/(ln(n)*np) (n=2 to ∞)

i had a similar question in which case i had
\sum1/(x*lnpx)

\intdx/(x*lnpx)
and there i simply said t=lnx dt=dx/x

\intdt/tp

and from there it was really simple, but in the case of this question i have been trying and trying and just can't get it
 
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Use the same substitution and write:

n^p = e^{p \ln n} = e^{pt}
 
i tried that, but i got stuck, didnt think it was the right way to go, can you help me continue??
for integration n=x

\intdx/(ln(x)*xp)
t=ln(x)
n=et
dt=dx/x

\intdt/(t*et(p-1)
now for conveniance i say q=p-1

\intdt/(t*etq)

how do i continue this integration?
 
Prove $$\int\limits_0^{\sqrt2/4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx = \frac{\pi^2}{8}.$$ Let $$I = \int\limits_0^{\sqrt 2 / 4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx. \tag{1}$$ The representation integral of ##\arcsin## is $$\arcsin u = \int\limits_{0}^{1} \frac{\mathrm dt}{\sqrt{1-t^2}}, \qquad 0 \leqslant u \leqslant 1.$$ Plugging identity above into ##(1)## with ##u...

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