I currently try to factor the composite number $$3^{130}+5^{130}+7^{130}$$ and wonder whether the quadratic sieve can be accelerated because of the "high" exponents. I know that for numbers of the form $\ a^b+c\ $ with large $b$ this is possible, but I am not sure aboth this case here. The usual quadratic sieve can still be applied since the number of decimal digits is "only" $\ 110\ $ , but I would appreciate a trick, if there is one.
I did not find a factor with ECM yet and expect a high smallest prime factor.