Good to know I’m not the only one with that particular mental block!

It is probably a common error. A while back when I mistakenly “corrected” a sentence of yours and wrote, “Táim ag foghlaim na huimhreacha …” nobody spotted my error even though there were several knowledgeable people who were actively participating on that thread.

The correction to my correction was:
Táim ag foghlaim na n-uimhreacha anois …

Anywhoo, misery loves company and I think we’ve got lots of company with this particular mental block 😉