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Vanilla 1.1.10 is a product of Lussumo. More Information: Documentation, Community Support.

• CommentRowNumber1.
• CommentAuthorUrs
• CommentTimeSep 18th 2012
• (edited Sep 18th 2012)

following public demand, I added to tensor product of chain complexes a detailed elementary discussion of the tensor product $I_\bullet \otimes I_\bullet$ of the (normalized) chain interval with itself, and how it gives chains on the cellular square: in Square as tensor product of interval with itself.

• CommentRowNumber2.
• CommentAuthorDmitri Pavlov
• CommentTimeMay 4th 2020

Unable to make the \begin{cases} … \end{cases} work. \array and \begin{aligned} do not work either.

The error messages are meaningless, I am giving up after several attempts.

• CommentRowNumber3.
• CommentAuthorDmitri Pavlov
• CommentTimeMay 4th 2020

Trying to resolve a problem with mysteriously disappearing text after a displayed formula $$…$$.

Appears to be a parser bug.

• CommentRowNumber4.
• CommentAuthorUrs
• CommentTimeMay 4th 2020

If you give me a pointer to the code on MO, I’ll try to convert it.

• CommentRowNumber5.
• CommentAuthorDmitri Pavlov
• CommentTimeMay 4th 2020
• (edited May 4th 2020)

The MathOverflow code is this one:

$$P(i,j;k) = \begin{cases} \mathbb{Z} & \mathrm{if\,\,} i+j=k, \\ \mathbb{Z} \oplus \mathbb{Z} & \mathrm{if\,\,} i+j=k+1, \\ \mathbb{Z} & \mathrm{if\,\,} i+j=k+2, \\ 0 & \mathrm{else}. \end{cases}$$

• CommentRowNumber6.
• CommentAuthorRichard Williamson
• CommentTimeMay 4th 2020
• (edited May 4th 2020)

Hi Dmitri, I am not sure what you were attempting, but I have modified the entry now to use more or less exactly this code, and it works fine. Double dollars should have a blank line before and after; maybe that was the cause of the problems you ran into. Itex2MML didn’t seem to like the \, inside the \mathrm, so I just added some space in a different way.