U61ttslengthLandttXzeroscons0U11ttU12isNatListU12ttttU21ttU22isNatU22ttttU31ttU32isNatListU32ttttU41ttU42isNatU42ttU43isNatIListU43ttttU51ttU52isNatU52ttU53isNatListU53ttttisNatttisNatU11isNatIListKindisNatU21isNatKindisNatIListU31isNatIListKindisNatIListttisNatIListU41andisNatKindisNatIListKindttisNatIListKindandisNatKindisNatKindttisNatKindisNatIListKindisNatKindisNatKindisNatListttisNatListU51andisNatKindlengthnil0lengthconsNU61andandisNatList2.1U61ttU61ttslengthLslengthU61ttLU61ttslengthttt21.14if standard then (var | con | (lpo || unfold[1] || (dp;(tdg | sccs | sc)*;(edg[2] | sccs | sc | sct | {ur?;lpo -dp -af[2]}restore | {ur?;matrix -dp -dim 2 -ib 2 -ob 2 -ur[2]}restore | uncurryx?;uncurryx -top )[10]*)!)) else if relative then (trivial | var | (unfold[2] || (( lpo -quasi | matrix -dim 2 -ib 2 -ob 3 | matrix -dim 3 -ib 2 -ob 2 | uncurryx )[10]*))) else fail