¨ applies a function to each 1 of the argument elements, so it is on APL+1. ⌶ looks like a Roman numeral 1, so it also lives on the 1, albeit in the shifted position. ¯, <, ≤, =, ≥, >, and ≠ form a block. The number line 1–9 (because 0 on the far right)...