17 .char \[or] \h'.1m'\Z'\D'l 0 -.675m''\h'.1m'
19 .\" This is designed so that \[ul], \[rn], and \[br] form corners.
20 .char \[br] \Z'\v'.25m'\D'R .04m -1m''
21 .char \[rn] \Z'\v'-.77m'\D'R .54m .04m''\h'.5m'
22 .char \[ul] \Z'\v'.23m'\D'R .54m .04m''\h'.5m'
24 .char \[ru] \Z'\v'-.02m'\D'R .54m .04m''\h'.5m'
26 .fchar \[OK] \s[\En[.s]*6u/10u]\[rs]\s[0]/
28 .fchar \[sqrtex] \[radicalex]