\mathbb{1} doesn't display numbers in the required font

[OlgaRedozubova]

I need to output the number in this format to the screen

Please advise me how to do this.

[dpvc]

The MathJax TeX fonts (the only font currently available in MathJax v3) do not include this glyph. The only option is to use

\unicode[STIXGeneral]{x1D7D9}

but this relies on your readers having the STIX fonts (or some other font containing this glyph) installed locally.

But since the "blackboard bold" font is a work-around used when writing with chalk on a blackboard to represent what would have been typeset as bold characters in print, perhaps you can use \mathbf{1}, which is what the blackboard-bold character is supposed to represent.

[dpvc]

I'm moving this to the main MathJax issue tracker, so it can be found more easily.