λδ digital library (LDDL)
Constant
![[butterfly]](http://helm.cs.unibo.it/lambdadelta/images/b5.png "\lambda\delta butterfly")
Informal description: ""
{λ[x:frac].λ[y:frac].λ[z:frac].λ[u:frac].λ[e:{(y).(x)}.eq].λ[f:{(u).(z)}.eq]}.<{({({({(y).(x)}.2y).((x).2x)}.ts).({({(z).(y).(x)}.2z).({(u).(z).(y).(x)}.1u)}.ts)}.ts).({({({(y).(x)}.2y).((x).2x)}.ts).({({(u).(z).(y).(x)}.2u).({(z).(y).(x)}.1z)}.ts)}.ts)}.is>.{(e).(f).(y).(x).(u).(z)}.t1 Validation parameters: sort hierarchy = "Z2", kernel options = ""
Last update: Sat, 12 Dec 2020 10:46:54 +0100
![[Spacer]](http://helm.cs.unibo.it/lambdadelta/images/rainbow.png "\lambda\delta rainbow rule")
![[Generated from XML via XSL]](http://helm.cs.unibo.it/lambdadelta/images/xml_xsl2.png "Generated from XML via XSL")
![[PNG used here]](http://helm.cs.unibo.it/lambdadelta/images/PNGnow2.png "PNG used here")
![[Viewable with any browser]](http://www.anybrowser.org/campaign/bvgraphics/abtfile.png "Viewable with any browser")