User peanut has been posting variations of the same question, getting some feedback, and then deleting. Ikve seen at least three or four times. The most recent one was deleted shortly after getting a
posted answer, undeleted by Xander, and now deleted by peanut again.
(actually, multiple delete-undelete-delete, probably to post comments and remove comments. At least two directed at me were removed in
@Ѕᴀᴀᴅ Questions should definitely not be deleted after receiving answers. But I don't see a problem in deleting a question after receiving comments.
The real problem with the question (like many solution verification questions) is that there can not much be said apart from “Yes, that is correct” – and that alone is not worth an answer.
In Murty and Cojocaru, we have the theorem: As $x\rightarrow\infty$,
$$\#\{n\le x: n \text{ and } n+2 \text{ have at most seven prime factors}\}\gg \frac{x}{(\log x)^2}$$
The proof uses Brun's sieve with $A:=\{n(n+2): n\le x\}$ $P$ being the set of primes, and $\omega(2) = 1$, $\omega(p)=2$, so t...
Let $f_1,...,f_m$ - be convex functions. Define function $g$ as:
$$g(x) = \inf_{x_1,...,x_m}\{f_1(x_1)+...+f_m(x_m)|\ x_1+...+x_m = x\}$$
Find $g^*(y)$ - conjugate of $g(x)$.
