ℜℜ BLACK-LETTER CAPITAL R
™™ TRADE MARK SIGN
ℵℵ ALEF SYMBOL
+ ⅛⅛ VULGAR FRACTION ONE EIGHTH
+ ⅜⅜ VULGAR FRACTION THREE EIGHTHS
+ ⅝⅝ VULGAR FRACTION FIVE EIGHTHS
+ ⅞⅞ VULGAR FRACTION SEVEN EIGHTHS
←← LEFTWARDS ARROW
↑↑ UPWARDS ARROW
→→ RIGHTWARDS ARROW
⌊⌊ LEFT FLOOR
⌋⌋ RIGHT FLOOR
⎪⎪ CURLY BRACKET EXTENSION
+ ⎯⎯ HORIZONTAL LINE EXTENSION
││ BOX DRAWINGS LIGHT VERTICAL
□□ WHITE SQUARE
◊◊ LOZENGE