Stage: 4 Challenge Level: 
A composite number is
one that is neither prime nor 1.
Show that 10201 is composite in any base.
Likewise show that 10101 is composite in any base.
Further Reading: Learn About Number Bases by Toni Beardon
Dynamical systems. Patterned numbers. Factorisation (algebraic). Mathematical reasoning & proof. Number theory. Stage 5 - Reviewed 2012. Number bases. Inequality/inequalities. Place value. Manipulating algebraic expressions/formulae.
Published November 2003,December 2003.
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