We are searching for the shapes with minimal area that can be covered by two different pentominoes, using an odd number of pentominoes. We'll accept solutions on the plane only. If you have better solutions, please send them to George Sicherman HERE.

Historical note: The first known appearance of this problem was in Issue 11 of Rodolfo Kurchan's Puzzle Fun in 1996. It presents solutions for 11 pairs of pentominoes, found by Rodolfo Kurchan, Gustavo Piñeiro, Pablo Coll, and Hector San Segundo.

Issue 13 presented new and improved solutions from Mike Reid and Pieter Torbijn. —George Sicherman

F5I5odd	F5L5odd	F5P5odd	F5N5odd	F5T5odd	F5U5odd
F5V5odd	F5W5odd	F5X5odd	F5Y5odd	F5Z5odd	I5L5odd
I5P5odd	I5N5odd	I5T5odd	I5U5odd	I5V5odd	I5W5odd
I5X5odd	I5Y5odd	I5Z5odd	L5P5odd	L5N5odd	L5T5odd
L5U5odd	L5V5odd	L5W5odd	L5X5odd	L5Y5odd	L5Z5odd
P5N5odd	P5T5odd	P5U5odd	P5V5odd	P5W5odd	P5X5odd
P5Y5odd	P5Z5odd	N5T5odd	N5U5odd	N5V5odd	N5W5odd
N5X5odd	N5Y5odd	N5Z5odd	T5U5odd	T5V5odd	T5W5odd
T5X5odd	T5Y5odd	T5Z5odd	U5V5odd	U5W5odd	U5X5odd
U5Y5odd	U5Z5odd	V5W5odd	V5X5odd	V5Y5odd	V5Z5odd
W5X5odd	W5Y5odd	W5Z5odd	X5Y5odd	X5Z5odd	Y5Z5odd

See also:
Pento-tro-dominoes
Pento-tetro-trominoes
Tetrominoes Challenge
Triple Pentominoes

LINKS:
Holeless Pentomino Odd Pairs
Pentabolo Odd Pairs
Pentahex Odd Pairs
Pentacube Odd Pairs
Visit the wonderful site of Jorge Luis Mireles (archived).
The new pages of Giovanni Resta.
The T.I.D. RONSE BELGIUM site (now K.S.O. Glorieux Ronse).