EPSOHQ

Permutation & Swap

Elements exchange positions according to a fixed rule. No new elements — just rearrangement.

Understanding this pattern

Permutation patterns rearrange elements within a fixed grid. Edges swap, quadrants rotate, or elements cycle through a defined order. The total number of elements stays constant — what changes is their configuration. These are among the most difficult patterns because the rule affects relationships between elements, not individual properties.

Example Question

Edge swap in 2x2 grid q04_swap_edges
Question 4 Options A B C D E
Correct answer: C

Pattern Rule

Each panel is a 2×2 grid containing one black dot, one hollow circle, one hollow triangle, and one empty cell. The black dot moves one corner clockwise per step: top-left → top-right → bottom-right → bottom-left → top-left. At each step, it swaps positions with the symbol or empty space in the destination cell; the other two cells remain unchanged.

Explanation

Option C is correct: it shows the hollow circle at top-left, the black dot at top-right, the empty bottom-left cell, and the hollow triangle at bottom-right. Option A duplicates panel 5. Option B has the triangle at top-left, circle at top-right, empty bottom-left, and dot at bottom-right. Option D omits the hollow circle and shows only the dot at top-right and triangle at bottom-right. Option E duplicates panel 4, with the circle at top-right, dot at bottom-left, and triangle at bottom-right.

How to spot it

  • Same elements present in every frame, but in different positions
  • Pairs of elements seem to swap places systematically
  • The overall "inventory" of shapes/colours stays constant

Common traps

  • Trying to track individual elements instead of the swap rule
  • Confusing which pair swaps — it may alternate between different pairs
  • Assuming a simple rotation when the rule is a more complex permutation

Related tags

permutation edge_swap grid_2x2

Question patterns using this concept (2)

q04_swap_edges q23_arrow_staircase