# Kronecker.jl - KroneckerSum

**URL:** <https://discourse.julialang.org/t/kronecker-jl-kroneckersum/117440>\
**Category:** General Usage\
**Tags:** question\
**Created:** [July 24, 2024, 7:34pm UTC](https://discourse.julialang.org/t/kronecker-jl-kroneckersum/117440 "2024-07-24T19:34:16Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![Domenico\_Lahaye](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/domenico_lahaye/32/203728_2.png) [@Domenico\_Lahaye](https://discourse.julialang.org/u/Domenico_Lahaye)\
**Post date:** [July 24, 2024, 7:34pm UTC](https://discourse.julialang.org/t/kronecker-jl-kroneckersum/117440/1 "2024-07-24T19:34:16Z")

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Hello,

Q1. Does the first equation at [kroneckersums](https://michielstock.github.io/Kronecker.jl/stable/man/kroneckersums/) contain a typo in the second term on the right-hand side (KroneckerSum =\> KroneckerProduct)?

Q2. Do (approximate) factorization methods exit for Kronecker sums?

Q3. Is my understanding correct that the matrix-vector product with Kronecker sum can be computed without explicitly forming the matrix?