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I have extended your definitions to have four times as many sequences (sorry to add a third set of definitions). If I am not mistaken there are exactly $10$ interesting repeated entries up to $10^{12}$, none of which affect your restricted case: You might find a few ideas here. This is just meant to reinforce the idea that there is no deep reason that coincidences could not occur, and a few do. But the numbers are so sparse that it seems reasonable that only finitely few do, except some obvious small identities.

The other repeats up to $10^{12}$ are $89=V_3(5)=U_2(9)$ along with $3191=U_5(5)=U_2(56)$ and $13201=V_5(7)=V_3(24).$

I have extended your definitions to have four times as many sequences (sorry to add a third set of definitions). If I am not mistaken there are exactly $11$ interesting repeated entries up to $10^{12}$, none of which affect your restricted case: You might find a few ideas here. This is just meant to reinforce the idea that there is no deep reason that coincidences could not occur, and a few do. But the numbers are so sparse that it seems reasonable that only finitely few do, except some obvious small identities.

The other repeats up to $10^{12}$ are $41=V_3(4)=U_2(6),\ 89=V_3(5)=U_2(9),\ 1189=V_3(11)=U_2(34)$ along with $3191=U_5(5)=U_2(56)$ and $13201=V_5(7)=V_3(24).$

I don't know that it matters, but we see from this (after more computation) that $\frac{U_i{m}}{V_i(m)}\approx\sqrt{\frac{m+2}{m-2}}$ where the approximation is quite good. For $m=5,6$ we have $\sqrt{\frac{m+2}{m-2}}=\sqrt{3},\sqrt{2}.$ Observe in the tables below that $U(5),V(5)$ give the numerators and denominators of alternate terms of the sequence $1/1,2/1, 5/3, 7/4, 19/11, 26/15, 71/41, 97/56, 265/153, 362/209,\cdots$ of convergents to $\sqrt{3}.$ Similarly, $U(6),V(6)$ give the numerators and denominators of alternate terms of the sequence $1/1,3/2,7/5,17/12,41/29,99/70,239/169,577/408,1393/985,\cdots$ of convergents to $\sqrt{2}.$ Similar things can be observed and explained. I'll only mention that half of the Fibonacci numbers are at $V(3)$ and another quarter at $U(7).$

Other thoughts: In a sense, $U(m)$ and $ V(m)$ are just scaled versions of the powers of $m$ so we kind of have the prime powers (twice). We now know for sure that the set of powers $m^i$ (starting at $2^4=16$) and the set of near powers $b^j\pm1$ ($i,j \ge 2$) are disjoint. There are many conjectures about the the growth rate of gaps.Your sets are sparser than these and even with four times as many entries as you are using there are few coincidences. One could consider other sequences given by the recurrence but with other initial conditions. I wondered why you chose exactly the ones you did. Is there an motivating problem? There are also other second order recurrences, including many with only one root larger than $1$ in absolute value. Namely: $W_{i+1}=mW_i+cW_{i-1}$ where $-(m+1) \lt c \lt m-1$.

I don't know that it matters, but we see from this (after more computation) that $\frac{U_i(m)}{V_i(m)}\approx\sqrt{\frac{m+2}{m-2}}$ where the approximation is quite good. For $m=4,6$ we have $\sqrt{\frac{m+2}{m-2}}=\sqrt{3},\sqrt{2}.$ Observe in the tables below that $U(4),V(4)$ give the numerators and denominators of alternate terms of the sequence $1/1,2/1, 5/3, 7/4, 19/11, 26/15, 71/41, 97/56, 265/153, 362/209,\cdots$ of convergents to $\sqrt{3}.$ Similarly, $U(6),V(6)$ give the numerators and denominators of alternate terms of the sequence $1/1,3/2,7/5,17/12,41/29,99/70,239/169,577/408,1393/985,\cdots$ of convergents to $\sqrt{2}.$ Similar things can be observed and explained. I'll only mention that, while the relation to $\sqrt{5}$ at $m=3$ is less obvious (though there) a consequence is that half of the Fibonacci numbers constitute $V(3)$ and another quarter constitute $U(7).$

Other thoughts: In a sense, $U(m)$ and $ V(m)$ are just scaled versions of the powers of $m$ so we kind of have the prime powers (twice). We now know for sure that the set of powers $m^i$ (starting at $2^4=16$) and the set of near powers $b^j\pm1$ ($i,j \ge 2$) are disjoint. There are many conjectures about the the growth rate of gaps.Your sets are sparser than these by a factor of two. Even with four times as many entries as you are using, so twice the density of the integer powers, there are few coincidences.

One could consider other sequences given by the same recurrence but with other initial conditions. That would provide the "missing" convergents and Fibonacci numbers. I wondered why you chose exactly the ones you did. Is there an motivating problem? There are also other second order recurrences with only one root larger than $1$ in absolute value. Namely: $W_{i+1}=mW_i+cW_{i-1}$ where $-(m+1) \lt c \lt m-1$.

Then the $U_i,V_i$ can be expressed as linear combinations of the roots $r=\frac{m \pm \sqrt{m^2-4}}{2}$ of $r^2-r+1=0.$ One of the roots is very close to $\frac{1}{m}$ and the other close to $m.$ SO, after a bit of computation,

$V_i(m)=\lfloor{\frac{m+2+\sqrt{m^2-4}}{2(m+2)} \left( \frac{m+\sqrt{m^2-4}}{m+2}\right)^n} \rceil$ where $\lfloor z\rceil$ means round to the nearest integer which in this case will be very close.(The distance from the nearest integer goes to $0$ like $\frac{1}{m^n}$)

I don't know that it matters, but we see from this (after more computation) that $\frac{U_i{m}}{V_i(m)}\approx\sqrt{\frac{m+2}{m-2}}$ where the approximation is fairly good:

Here are the first few terms of the first few of these series with terms over $1000000$ not shown. Notice a quarter of the Fibonacci numbers at $U(4)$ and another quarter at $V(3).$ Note too that the terms in $U(m)$ and in $V(m)$ grow very much like $m^i$ at least for $m$ not real small.

$\begin{array}{cccccccccc} 2&5&13&34&89&233&610&1597&4181& 10946\\\ 3&11&41&153&571&2131&7953&29681&110771& 413403\\\ 4&19&91&436&2089&10009&47956&229771&-&- \\\ 5&29&169&985&5741&33461&195025&-&-&- \\\ 6&41&281&1926&13201&90481&620166&-&-&- \\\ 7&55&433&3409&26839&211303&-&-&-&- \\\ 8&71&631&5608&49841&442961&-&-&-&- \\\ 9&89&881&8721&86329&854569&-&-&-&- \\\ 10&109&1189&12970&141481&-&-&-&-&- \\\ 11&131&1561&18601&221651&-&-&-&-&- \\\ 12&155&2003&25884&334489&-&-&-&-&- \\\ 13&181&2521&35113&489061&-&-&-&-&- \\\ 14&209&3121&46606&695969&-&-&-&-&- \\\ 15&239&3809&60705&967471&-&-&-&-&- \\\ 16&271&4591&77776&-&-&-&-&-&-\end{array}$

There are a few sporadic cases of $v=U_3(m)=U_2(m')$ These are for $(v,m,m')=(29,3,5),(71,4,8),(239,6,15),$$(60761,39,246),(2370059,133,1539)(6679639,188,2584)$

Note that each $U_2(m')=V_2(m'+1)$. Here is an analysis: To solve $m^3+m^2-2m-1=(m')^2+m'-1$ we can use the quadratic formula to solve $m'=\frac{-1+\sqrt{4m^3+4m^2-8m+1}}{2}$ SO the cubic under the radical must be a perfect square. This is a matter of looking for integer points on an elliptic curve for which there is a well developed theory (which I did not use.) One expects finitely many. One could check if the integer points given lead any others using the group law. It might be that this kind of analysis (which I did not really do here anyway) could be done for some $U_4,V_4,U_6,V_6.$

$239=U_3(6) \approx \frac{239+169\sqrt{2}}{2}\approx 239.001046$ and also $239=U_2(15)\approx \frac{239}{2}+\frac{209\sqrt{221}}{26} \approx 239.0003219.$ There does not seem to be anything deep here (that I see.) However the fact that the rational and irrational parts are nearly equal is not a coincidence.

Then the $U_i,V_i$ can be expressed as linear combinations of the roots $r=\frac{m \pm \sqrt{m^2-4}}{2}$ of $r^2-r+1=0.$ One of the roots is very close to $\frac{1}{m}$ and the other close to $m-\frac{1}{m}.$ SO, after a bit of computation,

$V_i(m)=\lfloor{\frac{m+2+\sqrt{m^2-4}}{2(m+2)} \left( \frac{m+\sqrt{m^2-4}}{m+2}\right)^n} \rceil$ where $\lfloor z\rceil$ means round to the nearest integer, which in this case will be very close.(The distance from the nearest integer goes to $0$ like $\frac{1}{m^n}$). The approximation will be of the form $U_i(m)=v \approx \frac{v}{2}+\frac{p\sqrt{m^2-4}}{q}$

I don't know that it matters, but we see from this (after more computation) that $\frac{U_i{m}}{V_i(m)}\approx\sqrt{\frac{m+2}{m-2}}$ where the approximation is quite good. For $m=5,6$ we have $\sqrt{\frac{m+2}{m-2}}=\sqrt{3},\sqrt{2}.$ Observe in the tables below that $U(5),V(5)$ give the numerators and denominators of alternate terms of the sequence $1/1,2/1, 5/3, 7/4, 19/11, 26/15, 71/41, 97/56, 265/153, 362/209,\cdots$ of convergents to $\sqrt{3}.$ Similarly, $U(6),V(6)$ give the numerators and denominators of alternate terms of the sequence $1/1,3/2,7/5,17/12,41/29,99/70,239/169,577/408,1393/985,\cdots$ of convergents to $\sqrt{2}.$ Similar things can be observed and explained. I'll only mention that half of the Fibonacci numbers are at $V(3)$ and another quarter at $U(7).$

Here are the first few terms of $U(m)$ then $v(m)$ for $3 \le m \le 17.$ Values over $1000000$ are not shown. As just mentioned, numerators and denominators of convergents to $\sqrt{2}$ show up as $U(6),V(6)$ respectively with growth rate $(1+\sqrt{2})^2=3+2\sqrt{2}=5.828\cdots \approx 6-1/6 \approx 6$ This illustrates that the terms in $U(m)$ and in $V(m)$ grow very much like $m^i$. More precisely, they grow like $(\frac{m+\sqrt{m^2-4}}{2})^n \approx (m-\frac1m)^n.$

$\begin{array}{cccccccccc} 2&5&13&34&89&233&610&1597&4181& 10946\\\ 3&11&41&153&571&2131&7953&29681&110771& 413403\\\ 4&19&91&436&2089&10009&47956&229771&-&- \\\ 5&29&169&985&5741&33461&195025&-&-&- \\\ 6&41&281&1926&13201&90481&620166&-&-&- \\\ 7&55&433&3409&26839&211303&-&-&-&- \\\ 8&71&631&5608&49841&442961&-&-&-&- \\\ 9&89&881&8721&86329&854569&-&-&-&- \\\ 10&109&1189&12970&141481&-&-&-&-&- \\\ 11&131&1561&18601&221651&-&-&-&-&- \\\ 12&155&2003&25884&334489&-&-&-&-&- \\\ 13&181&2521&35113&489061&-&-&-&-&- \\\ 14&209&3121&46606&695969&-&-&-&-&- \\\ 15&239&3809&60705&967471&-&-&-&-&- \\\ 16&271&4591&77776&-&-&-&-&-&- \\\ 17&305&5473&98209&-&-&-&-&-&-\end{array}$

There are six sporadic cases of $v=U_3(m)=U_2(m').$ Equivalently, $U_3(m)=V_2(m'+1)$. These are for $(v,m,m')=(29,3,5),(71,4,8),(239,6,15),$$(60761,39,246),(2370059,133,1539)(6679639,188,2584).$ There might be more, but I doubt it. This is complete up to $v=25 \cdot 10^{18}.$

Here is an analysis: To solve $m^3+m^2-2m-1=(m')^2+m'-1$ we can use the quadratic formula to solve $m'=\frac{-1+\sqrt{4m^3+4m^2-8m+1}}{2}$ SO the cubic under the radical must be a perfect square. This is a matter of looking for integer points on an elliptic curve for which there is a well developed theory (which I did not use.) One expects finitely many. One could check if the integer points given lead any others using the group law. It might be that this kind of analysis (which I did not really do here anyway) could also be done for some $U_4,V_4,U_6,V_6.$

$239=U_3(6) \approx \frac{239+169\sqrt{2}}{2}\approx 239.001046$ and also $239=U_2(15)\approx \frac{239}{2}+\frac{209\sqrt{221}}{26} \approx 239.0003219.$ I do not see anything deep here. However the fact that the rational and irrational parts are nearly equal is not a coincidence.