Originally Posted by eyeomegasquared

Yeah, I give up on knowing what sqrl means. There is too much misinformation. But I read it aloud as a sequence of letters: S-Q-R-L. So according to section 10.9 of the Chicago Manual of Style, it is proper to use the article "an" rather than "a" for preceding sqrl.

From CMoS:
10.9“A,” “an,” or “the” preceding an abbreviation

When an abbreviation follows an indefinite article, the choice of a or an is determined by the way the abbreviation would be read aloud. Acronyms are read as words and are rarely preceded by a, an, or the (“member nations of NATO”), except when used adjectivally (“a NATO initiative”). Initialisms are read as a series of letters and are often preceded by an article (“member nations of the EU”). See 10.2; see also 7.44.

an HMO
a UFO