MHB Is the Sum of n^2 Terms in an Arithmetic Sequence Limited to 1?

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How many different arithmetic sequences have the sum of the first n terms n^2?
solution an= 2n-1.Does that mean there is only one arithmetic sequence?
 
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If the sum of the first $n$ terms must equal $n^2$ for all $n$, then yes, such sequence is unique. To see why, write the sum of $n$ terms using the first term $a_1$ and the difference $d$. This is going to be a quadratic polynomial. Its leading coefficient has to be equal to 1, and the other two have to be 0.
 
The first term must be 1. The second term must satisfy 1+ x= 4 so x= 3. The third term must satisfy 4+ x= 9 so x=5. The fourth term must satisfy 9+ x= 16 so x= 7.. The fifth term must satisfy 16+ X= 25 so x=9. Do you see a pattern?
 
Insights auto threads is broken atm, so I'm manually creating these for new Insight articles. In Dirac’s Principles of Quantum Mechanics published in 1930 he introduced a “convenient notation” he referred to as a “delta function” which he treated as a continuum analog to the discrete Kronecker delta. The Kronecker delta is simply the indexed components of the identity operator in matrix algebra Source: https://www.physicsforums.com/insights/what-exactly-is-diracs-delta-function/ by...
Fermat's Last Theorem has long been one of the most famous mathematical problems, and is now one of the most famous theorems. It simply states that the equation $$ a^n+b^n=c^n $$ has no solutions with positive integers if ##n>2.## It was named after Pierre de Fermat (1607-1665). The problem itself stems from the book Arithmetica by Diophantus of Alexandria. It gained popularity because Fermat noted in his copy "Cubum autem in duos cubos, aut quadratoquadratum in duos quadratoquadratos, et...
I'm interested to know whether the equation $$1 = 2 - \frac{1}{2 - \frac{1}{2 - \cdots}}$$ is true or not. It can be shown easily that if the continued fraction converges, it cannot converge to anything else than 1. It seems that if the continued fraction converges, the convergence is very slow. The apparent slowness of the convergence makes it difficult to estimate the presence of true convergence numerically. At the moment I don't know whether this converges or not.

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