This ratio equals (1 + √5) / 2 and divides a line so that whole-to-longer equals longer-to-shorter.

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Your new ahaThe Golden Ratio

The Golden Ratio: A proportion often described as uniquely pleasing to the eye. Source: Golden ratio ↗

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04These integers greater than one have exactly two positive divisors: one and themselves.RECALL
Prime Numbers
Prime numbers have exactly two positive divisors: one and themselves. The number one is not prime.
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05Starting with 0 and 1, each term of this sequence is the sum of the previous two.RECALL
The Fibonacci Sequence
The Fibonacci sequence, where each term sums the two before it, shows up in patterns like sunflower spirals.
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06These positive integers equal the sum of their positive divisors excluding themselves; 6 and 28 are examples.RECALL
Perfect Numbers
Perfect numbers equal the sum of their positive divisors excluding themselves: 6 = 1 + 2 + 3.
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