Well, 11 is an odd number and a prime number.
To be honest, compared to other interesting numbers, I don't know much about 11 (number) apart from easier (and sort of interesting) when applying multiplication or division.
Oh, speaking about algorithm, unlike today's lucky American school kids, I did the math with pen and paper
, not calculators. Definitely no graphic calculators. We calculated interested points and hand draw the mathematical graph.
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