I'm in the same boat. The multiplication tables for me in that zone are constructs from other principles. :) So, Fives and Nines are easy and I can derive the S

I'm in the same boat. The multiplication tables for me in that zone are constructs from other principles. :) So, Fives and Nines are easy and I can derive the Sixes Sevens and Eights from those. It's definitely extra steps. I think I'm reasonably good at the sort of mental arithmetic described in another post, Those particular operations just remain as symbols until I absolutely need to define them more precisely. I don't have a problem with 11s and 12s, but 5s and Rs trip me up. The way that our brains process symbols is fascinating. If anyone out there has any literature or reading on this, I'd be interested. Especially, as related to ADHD/Autism.