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DoubleStruckCapitalA ... DoubleStruckCapitalZ
... \[DoubleStruckCapitalA] ... \[DoubleStruckCapitalZ]
Aliases: dsA through dsZ.
Treated as distinct characters rather than style modifications of ordinary letters.
, , , , , are used respectively to denote the sets of natural numbers, integers, rationals, reals, complex numbers and quaternions.
Contiguous character codes from the private Unicode character range are used, even though a few capital double-struck characters are included in ordinary Unicode.
See The Mathematica Book: Section 3.10.3.
See also: \[GothicCapitalA] , \[ScriptCapitalA] , etc.