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show/hide this revision's text 2 Minor typographic improvement

The notation $M^{\oplus n}$ and $M^{\otimes n} $ to denote, respectively, nth direct sum and nth tensor product.

The notation $X \pi mathbin{\pi} Y$ to denote product of objects in an abstract category, and the analogous with the "upside down $\pi$" for coproduct. I once have seen this being used by B.Keller in a talk. It'd be nice to have a smaller $\Pi$ (resp. $\amalg$) symbol instead.

    Post Made Community Wiki by Ben Webster
show/hide this revision's text 1

The notation $M^{\oplus n}$ and $M^{\otimes n} $ to denote, respectively, nth direct sum and nth tensor product.

The notation $X \pi Y$ to denote product of objects in an abstract category, and the analogous with the "upside down $\pi$" for coproduct. I once have seen this being used by B.Keller in a talk. It'd be nice to have a smaller $\Pi$ (resp. $\amalg$) symbol instead.