Stage: 5 Challenge Level: 
Rushaan, Jacquin and Spencer from the Cape Academy sent us in their complete sorted proof
Patterned numbers. Dynamical systems. Mathematical reasoning & proof. Summation of series. Stage 5 - Reviewed 2012. Manipulating algebraic expressions/formulae. Interactivities. Number theory. Inequality/inequalities. Geometric sequence.
Published June 2001.
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