Group algebra of permutation group, error

asked 2021-11-19 16:24:51 +0100

JTS gravatar image

updated 2021-11-19 16:26:05 +0100

Why does not


work when


does work?

The first command gives a long error message, terminating with the slightly bizzare

RuntimeError: There is a bug in the coercion code in Sage.
Both x (=()) and y (=()) are supposed to have identical parents but they don't.
In fact, x has parent 'Permutation Group with generators [(2,3,4), (1,2,3)]'
whereas y has parent 'Permutation Group with generators [(2,3,4), (1,2,3)]'
Original elements () (parent Permutation Group with generators [(2,3,4), (1,2,3)]) and () (parent Permutation Group with 
generators [(2,3,4), (1,2,3)]) and maps
<class 'NoneType'> None
<class 'sage.structure.coerce_maps.DefaultConvertMap_unique'> (map internal to coercion system -- copy before use)
Coercion map:
From: Permutation Group with generators [(2,3,4), (1,2,3)]
To:   Permutation Group with generators [(2,3,4), (1,2,3)]
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It says it's a bug. So it needs to be reported.

Max Alekseyev gravatar imageMax Alekseyev ( 2021-11-19 18:04:06 +0100 )edit