A364607 Denominations of a 4-coin system that returns the fewest coins in change on average.

1, 5, 18, 25

Offset: 1

Author

Thomas Young, Aug 06 2023

Keywords

• nonn
• full
• fini

Comments

In 1995, Thomas Young, along with students Jeff Greenfield, Joe Culbert, and David Raabe, explored the idea of the best 4-coin system for making change for a dollar. They assumed that each value for change (from 1 cent to 99 cents) was equally likely and, using an original Turbo Pascal program, calculated the average number of coins returned for every possible set of 4 coin denominations. Their result was announced via the essay, "Change the Dime not the Dollar."

The average number of coins required to return 1..99 cents is A339333(99,4)/99 = 389/99. - Pontus von Brömssen, Aug 13 2023

Links

• Thomas Young, A Turbo Pascal program to find the optimal coin system.
• Thomas Young, Change the Dime Not the Dollar.

Crossrefs

Cf. A208953, A339333, A366013.