“Unfold” the coin delta in a series of single-coin moves…

# Always Three

*|*by Serhiy Grabarchuk Jr

By moving one coin at a time, reach the Goal position so that after each move…

# The Coined Rows

*|*by Serhiy Grabarchuk

Eight coins are arranged into 4 rows of three coins each. Move just two coins to get…

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# Olympic Coins

*|*by Serhiy Grabarchuk Jr

Change a stylized “Olympic” pattern into the one shown in the Goal. Single-coin sliding moves to do that.

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# The GO Challenge

*|*by Serhiy Grabarchuk

Convert the “G” letter into the “O” letter. A move consists of sliding a coin to a new position where it has to touch at least two other coins.

# In Puzzleland

*|*by Sam Loyd

Nine coins placed in a 3×3 array, produce 8 rows of three coins each – three horizontal rows, three vertical rows and two main diagonals. Move the minimum possible number to…

# Coins & Triangles

*|*by Kobon Fujimura

Fifteen equilateral triangles can be spotted in this arrangement. What is the minimum number of coins to be removed in order to get rid of all the equilateral triangles in it?

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# Wi-Fi Switch

*|*by Serhiy Grabarchuk Jr

Convert the “W” letter into the “F” letter. A move consists of sliding a coin to a new position where it has to touch at least two other coins.

# Nob’s H-2-O

*|*by Nob Yoshigahara

Convert the “H” letter into the “O” letter – a 3×3 coin square without the central coin. A move consists of sliding a coin to a new position where it has to touch at least two other coins.

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# The Six Pennies

*|*by Henry E. Dudeney

Turn the two rows of coins into the coin circle in just three moves. A move consists of sliding a coin to a new position where it has to touch at least two other coins.

# Coin Cup

*|*by Serhiy Grabarchuk Jr

Move just two coins to turn a coin cup upside-down. The restriction is that after each move a moved coin should touch two other ones.