| 1094 | Subtraction and square root in base‑eight | Deep | base conversionsquare root | |
| 1106 | Nonary to quinary | Deep | base conversionpositional notation | |
| 1107 | Septenary to duodecimal powers | Deep | base conversionpositional notation | |
| 1116 | Radix for arithmetic progression | Deep | base conversionarithmetic progression | |
| 1119 | Perfect square for large radices | Deep | perfect squareradix representation | |
| 1120 | Square with invariant root digits | Deep | perfect squareradix invariance | |
| 1121 | Universal perfect cube | Deep | perfect cuberadix representation | |
| 1509 | LCM of several base‑six numbers | Deep | LCMbase arithmetic | |