Single-digit time signature with different number

[M Watts]

I figured something out myself :)

Now that Sigfrid Karg-Elert's works are public domain, him having been 
dead for over 70 years, I'm fiddling with his 25 Caprices & Sonata for 
solo saxophone (op. 153).

The Sonata's 2nd movement is in fast 3/4 time, with one beat to the bar, 
and its time signature is a simple number "1".

I found that using

\override Staff.TimeSignature #'style = #'single-digit (which I've used 
before), and

\set Staff.timeSignatureFraction = #'(1 . 4)

produces exactly the desired result.

So thanx again for this wonderful software.