Henry Ernest Dudeney/Puzzles and Curious Problems/249 - Odds and Evens

Puzzles and Curious Problems by Henry Ernest Dudeney: $249$

Odds and Evens

Place eight counters in a pile on the middle circle so that they shall be in proper numerical order, with $1$ on the top and $8$ on the bottom.

It is required to transfer $1$, $3$, $5$, $7$ to the circle marked "Odds", and $2$, $4$, $6$, $8$ to the circle marked "Evens".

You can only move one counter at a time from circle to circle, and you must never place a number on a smaller number,

nor an odd number and an even number together on the same circle.

What are the fewest possible moves?

Sources

• 1932: Henry Ernest Dudeney: Puzzles and Curious Problems ... (previous) ... (next): Moving Counter Problems: $249$. -- Odds and Evens
• 1968: Henry Ernest Dudeney: 536 Puzzles & Curious Problems ... (previous) ... (next): Geometrical Problems: Moving Counter Puzzles: $373$. Odds and Evens