Define $p_n\#= p_n p_{n-1} \cdots p_1$ for $n = 0$ to be $1$, then we have a function:
$$ N : \Bbb{Z} \to \Bbb{Z}, \\ N(x) = \left |-1/2 + \sum_{d\ \mid\ p_n\#} (-1)^{\omega d} \sum_{r^2 = 1 \mod d} \left\lfloor \frac{x - r}{d}\right\rfloor \right |\\ \text{ with } n = n(x) = \pi(\sqrt{|x| + 1}) $$
where $\pi$ is the usual prime counter.
Here is the output of SymPy code that computes $N(x)$ and $N(-x)$ side-by-side:
N(-0) = 0.5; N(0) = 0.5
N(-1) = 1.5; N(1) = 0.5
N(-2) = 2.5; N(2) = 1.5
N(-3) = 1.5; N(3) = 1.5
N(-4) = 1.5; N(4) = 2.5
N(-5) = 2.5; N(5) = 2.5
N(-6) = 2.5; N(6) = 3.5
N(-7) = 3.5; N(7) = 3.5
N(-8) = 1.5; N(8) = 1.5
N(-9) = 1.5; N(9) = 1.5
N(-10) = 1.5; N(10) = 1.5
N(-11) = 1.5; N(11) = 1.5
N(-12) = 1.5; N(12) = 2.5
N(-13) = 2.5; N(13) = 2.5
N(-14) = 2.5; N(14) = 2.5
N(-15) = 2.5; N(15) = 2.5
N(-16) = 2.5; N(16) = 2.5
N(-17) = 2.5; N(17) = 2.5
N(-18) = 2.5; N(18) = 3.5
N(-19) = 3.5; N(19) = 3.5
N(-20) = 3.5; N(20) = 3.5
N(-21) = 3.5; N(21) = 3.5
N(-22) = 3.5; N(22) = 3.5
N(-23) = 3.5; N(23) = 3.5
N(-24) = 2.5; N(24) = 2.5
N(-25) = 2.5; N(25) = 2.5
N(-26) = 2.5; N(26) = 2.5
N(-27) = 2.5; N(27) = 2.5
N(-28) = 2.5; N(28) = 2.5
N(-29) = 2.5; N(29) = 2.5
N(-30) = 2.5; N(30) = 3.5
N(-31) = 3.5; N(31) = 3.5
N(-32) = 3.5; N(32) = 3.5
N(-33) = 3.5; N(33) = 3.5
N(-34) = 3.5; N(34) = 3.5
N(-35) = 3.5; N(35) = 3.5
N(-36) = 3.5; N(36) = 3.5
N(-37) = 3.5; N(37) = 3.5
N(-38) = 3.5; N(38) = 3.5
N(-39) = 3.5; N(39) = 3.5
N(-40) = 3.5; N(40) = 3.5
N(-41) = 3.5; N(41) = 3.5
N(-42) = 3.5; N(42) = 4.5
N(-43) = 4.5; N(43) = 4.5
N(-44) = 4.5; N(44) = 4.5
N(-45) = 4.5; N(45) = 4.5
N(-46) = 4.5; N(46) = 4.5
N(-47) = 4.5; N(47) = 4.5
N(-48) = 4.5; N(48) = 4.5
N(-49) = 4.5; N(49) = 4.5
N(-50) = 4.5; N(50) = 4.5
N(-51) = 4.5; N(51) = 4.5
N(-52) = 4.5; N(52) = 4.5
N(-53) = 4.5; N(53) = 4.5
N(-54) = 4.5; N(54) = 4.5
N(-55) = 4.5; N(55) = 4.5
N(-56) = 4.5; N(56) = 4.5
N(-57) = 4.5; N(57) = 4.5
N(-58) = 4.5; N(58) = 4.5
N(-59) = 4.5; N(59) = 4.5
N(-60) = 4.5; N(60) = 5.5
N(-61) = 5.5; N(61) = 5.5
N(-62) = 5.5; N(62) = 5.5
N(-63) = 5.5; N(63) = 5.5
N(-64) = 5.5; N(64) = 5.5
N(-65) = 5.5; N(65) = 5.5
N(-66) = 5.5; N(66) = 5.5
N(-67) = 5.5; N(67) = 5.5
N(-68) = 5.5; N(68) = 5.5
N(-69) = 5.5; N(69) = 5.5
N(-70) = 5.5; N(70) = 5.5
N(-71) = 5.5; N(71) = 5.5
N(-72) = 5.5; N(72) = 6.5
N(-73) = 6.5; N(73) = 6.5
N(-74) = 6.5; N(74) = 6.5
N(-75) = 6.5; N(75) = 6.5
N(-76) = 6.5; N(76) = 6.5
N(-77) = 6.5; N(77) = 6.5
N(-78) = 6.5; N(78) = 6.5
N(-79) = 6.5; N(79) = 6.5
N(-80) = 6.5; N(80) = 6.5
N(-81) = 6.5; N(81) = 6.5
N(-82) = 6.5; N(82) = 6.5
N(-83) = 6.5; N(83) = 6.5
N(-84) = 6.5; N(84) = 6.5
N(-85) = 6.5; N(85) = 6.5
N(-86) = 6.5; N(86) = 6.5
N(-87) = 6.5; N(87) = 6.5
N(-88) = 6.5; N(88) = 6.5
N(-89) = 6.5; N(89) = 6.5
N(-90) = 6.5; N(90) = 6.5
N(-91) = 6.5; N(91) = 6.5
N(-92) = 6.5; N(92) = 6.5
N(-93) = 6.5; N(93) = 6.5
N(-94) = 6.5; N(94) = 6.5
N(-95) = 6.5; N(95) = 6.5
N(-96) = 6.5; N(96) = 6.5
N(-97) = 6.5; N(97) = 6.5
N(-98) = 6.5; N(98) = 6.5
N(-99) = 6.5; N(99) = 6.5
N(-100) = 6.5; N(100) = 6.5
N(-101) = 6.5; N(101) = 6.5
N(-102) = 6.5; N(102) = 7.5
As you can see, it doesn't quite satisfy certain types of norms' axiom $N(-x) = N(x)$. Since at the twin prime averages $x$ we have that $N(-x) +1 = N(x)$. However, under the assumption that the twin primes end, we must have that for sufficiently large $x \geq 0$, $x \in \Bbb{Z}$ that $N(x) = N(-x)$.
Remark. We may also take $N : \Bbb{R} \to \Bbb{Z}$ to be the function (domain is $\Bbb{R}$) and the above should still hold. So that gives us the freedom to work with either an abelian group $\Bbb{Z}$ or a vector space $\Bbb{R}$.
Now also under the assumption that the twin primes end, we must have that for sufficiently large $x, y \geq 0$ that $N(x + y) \leq N(x) + N(y)$. This is because under that assumption, we have that $N(x)$ eventually equals $0$ and so of course $0 = N(x + y)\leq N(x) + N(y)$ as $N(x) \geq 0$ in general.
Question. If we can show that $N(x)$ forms a pseudonorm for sufficiently large inputs and we define under similar "sufficiently large inputs" a pseudometric via $d(x,y) = N(x - y)$. And, we know that $N(x)$ is continuous in a given topology (it's likely continuous in the Furstenberg topology), then can we conclude that the pseudometric topology induced by $N$ is indeed the same as the Furstenberg topology?
Easier Related Question. Forget about "sufficiently large inputs" in the previous question. If $N$ were a usual pseudonorm, and we have proven that $N(x)$ is a continuous function $\Bbb{Z} \to \Bbb{Z}$ (e.g. under Furstenberg's topology), then can we conclude that the pseudometric topology induced by $d(x,y) = N(x-y)$ coincides with the given topology on $\Bbb{Z}$?