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

• CommentRowNumber1.
• CommentAuthorUrs
• CommentTimeSep 2nd 2012
• (edited Sep 26th 2012)

added a little bit more to split exact sequence.

• CommentRowNumber2.
• CommentAuthorUrs
• CommentTimeSep 26th 2012

Added statement and proof of the little lemma that an SES with first object injective splits.

• CommentRowNumber3.
• CommentAuthorGuest
• CommentTimeSep 25th 2019
I don't think one needs the 'finitely generated' claim on lemma 2.2. For instance, see

https://math.stackexchange.com/questions/382093/a-long-exact-sequence-of-free-abelian-group-is-the-direct-sum-of-very-short-exac
• CommentRowNumber4.
• CommentAuthorTodd_Trimble
• CommentTimeSep 25th 2019

Yes, you’re certainly right, Guest. (Or at least right if the axiom of choice is assumed.) I don’t know what the author may have been thinking.

I’ll fix this.

• CommentRowNumber5.
• CommentAuthorTodd_Trimble
• CommentTimeSep 25th 2019

Fixed a statement in response to discussion.

• CommentRowNumber6.
• CommentAuthorGuest
• CommentTimeJun 4th 2022

Elías:

There is a typo in the proof of Lemma 1.2. The last sentence should be “the implication that the first condition also implies the third (…)”