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Why Is $e^{\pi\sqrt{232}}$ an Almost Integer?

We have already discussed why $e^{(\pi\sqrt{163})}$ is an almost integer.

Why are powers of $\exp(\pi\sqrt{163})$ almost integers?

Basically $j(\frac{1+\sqrt{-163}}{2} ) \simeq 744 - e^{\pi\sqrt{163}}$, where $j(\frac{1+\sqrt{-163}}{2} )$ is a rational integer.

But $j(\sqrt {\frac{-232}{2}})$ and $j(\sqrt {\frac{-232}{4}})$ are not integers. They are algebraic integers of degree $2$, but they are also almost integers themselves. The same phenomenon happens with Class $2$ numbers $88$ and $148$.

Is there another modular function that explains why these numbers are almost integers?

Steven Heston
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