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Feb 5 at 17:39 vote accept Pascal Ochem
S Feb 4 at 15:46 history suggested CommunityBot CC BY-SA 4.0
mentioning that $p$ itself should be small.
Feb 4 at 8:06 review Suggested edits
S Feb 4 at 15:46
S Feb 4 at 5:27 history suggested J. W. Tanner
Added perfect-numbers tag
Feb 4 at 1:09 review Suggested edits
S Feb 4 at 5:27
Feb 3 at 19:19 answer added JoshuaZ timeline score: 3
Feb 3 at 4:11 comment added Daniel Weber We have $\Psi(x, \log^2 x) = x^{\frac12 + o(1)}$, which is also the number of values of $p^a + 1 \leq x$ for even $a$, so heuristically by the birthday paradox we should expect to find a collision around this $\log^2 x$. For $10^{62}$ this is around 20500. I don't have any idea how we could locate this collision, though
Feb 3 at 4:04 comment added Daniel Weber If we look at $p^a + 1 = p_1^{a_1} p_2^{a_2} \cdots$ then from the abc conjecture we should have $p^{a-1} \lesssim p_1 p_2 \cdots$, and additionally it can't contain any primes which are $3 \pmod 4$, so you get a lower bound of about 317.
Feb 3 at 2:36 history asked Pascal Ochem CC BY-SA 4.0