I wish I could tell you what I saw and why it came to me. Brains are amazing and varied things. Some scary-smart people claim they see colors in numbers and that that simplifies existence. People are both funny and entertaining...and then we die.
It’s called synaesthesia. Everybody has it to at least a minor degree, I’ve come to believe. Very prominent examples of it are usually found among musicians, artists and writers, those who depend upon creativity. If you’re running into mathematicians who are willing to admit to such an unconventional thing, they’re pretty secure. Math comes full circle to music and music to math. Are they also musicians by chance?