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1. • CommentRowNumber1.
   • CommentAuthorUrs
   • CommentTimeFeb 11th 2012
   • PermaLink
   Author: Urs
   Format: MarkdownItexstarted something basic at _[[Steenrod square]]_

   started something basic at Steenrod square

2. • CommentRowNumber2.
   • CommentAuthorUrs
   • CommentTimeNov 15th 2013
   • PermaLink
   Author: Urs
   Format: MarkdownItexadded to _[[Steenrod square]]_ the explicit construction in terms of [[extended powers]], in a new section [here](http://ncatlab.org/nlab/show/Steenrod+square#DefinitionInTermsOfExtendedSquares).

   added to Steenrod square the explicit construction in terms of extended powers, in a new section here.

3. • CommentRowNumber3.
   • CommentAuthorUrs
   • CommentTimeFeb 19th 2018
   • PermaLink
   Author: Urs
   Format: MarkdownItexI have made explicit the Adem relation for postcomposition with $Sq^1$: [here](https://ncatlab.org/nlab/show/Steenrod+square#CompositionWithSq1)

   I have made explicit the Adem relation for postcomposition with $Sq^1$: here

4. • CommentRowNumber4.
   • CommentAuthorUrs
   • CommentTimeSep 2nd 2020
   • (edited Sep 2nd 2020)
   • PermaLink
   Author: Urs
   Format: MarkdownItexadded publication details and jstor-links to: * [[Norman Steenrod]], _Products of cocycles and extensions of mappings_, Annals of Mathematics Second Series, Vol. 48, No. 2 (Apr., 1947), pp. 290-320 ([jstor:1969172](https://www.jstor.org/stable/1969172)) * [[Norman Steenrod]], [[David Epstein]], _Cohomology operations_, Annals of Mathematics Studies, Princeton University Press (1962) ([jstor:j.ctt1b7x52h](https://www.jstor.org/stable/j.ctt1b7x52h)) <a href="https://ncatlab.org/nlab/revision/diff/Steenrod+square/19">diff</a>, <a href="https://ncatlab.org/nlab/revision/Steenrod+square/19">v19</a>, <a href="https://ncatlab.org/nlab/show/Steenrod+square">current</a>

   added publication details and jstor-links to:

   • Norman Steenrod, Products of cocycles and extensions of mappings, Annals of Mathematics Second Series, Vol. 48, No. 2 (Apr., 1947), pp. 290-320 (jstor:1969172)

   • Norman Steenrod, David Epstein, Cohomology operations, Annals of Mathematics Studies, Princeton University Press (1962) (jstor:j.ctt1b7x52h)

   diff, v19, current

5. • CommentRowNumber5.
   • CommentAuthornLab edit announcer
   • CommentTimeNov 19th 2020
   • PermaLink
   Author: nLab edit announcer
   Format: MarkdownItexfixed grading (Sq^2n adds +2n) Anonymous <a href="https://ncatlab.org/nlab/revision/diff/Steenrod+square/20">diff</a>, <a href="https://ncatlab.org/nlab/revision/Steenrod+square/20">v20</a>, <a href="https://ncatlab.org/nlab/show/Steenrod+square">current</a>

   fixed grading (Sq^2n adds +2n)

   Anonymous

   diff, v20, current

6. • CommentRowNumber6.
   • CommentAuthorUrs
   • CommentTimeJan 17th 2023
   • PermaLink
   Author: Urs
   Format: MarkdownItexadded the following reference also here: * [[David Wärn]], Section 4.4 of: _Eilenberg-MacLane spaces and stabilisation in homotopy type theory_ &lbrack;[arXiv:2301.03685](https://arxiv.org/abs/2301.03685)&rbrack; (Incidentally, the nLab is extremely sluggish to me since last night, each page load at the verge of timing out. Had contacted the technical team about it, but no reply yet. But I guess I am not the only one experiencing this issue?) <a href="https://ncatlab.org/nlab/revision/diff/Steenrod+square/26">diff</a>, <a href="https://ncatlab.org/nlab/revision/Steenrod+square/26">v26</a>, <a href="https://ncatlab.org/nlab/show/Steenrod+square">current</a>

   added the following reference also here:

   • David Wärn, Section 4.4 of: Eilenberg-MacLane spaces and stabilisation in homotopy type theory [arXiv:2301.03685]

   (Incidentally, the nLab is extremely sluggish to me since last night, each page load at the verge of timing out. Had contacted the technical team about it, but no reply yet. But I guess I am not the only one experiencing this issue?)

   diff, v26, current

7. • CommentRowNumber7.
   • CommentAuthorDavid_Corfield
   • CommentTimeJan 17th 2023
   • PermaLink
   Author: David_Corfield
   Format: MarkdownItexAll is working speedily for me.

   All is working speedily for me.

8. • CommentRowNumber8.
   • CommentAuthorUrs
   • CommentTimeJan 17th 2023
   • PermaLink
   Author: Urs
   Format: MarkdownItexYes, strange, that's what I also hear from the technical team. For me the problem persisted, on different devices and networks, from last evening to this morning. Then it went away.

   Yes, strange, that’s what I also hear from the technical team.

   For me the problem persisted, on different devices and networks, from last evening to this morning. Then it went away.