# What this figure presents?

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flyskyposted 4 years ago

What this figure presents?

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john000posted 4 years ago

Looks like a dog to me. He appears to be sniffing. ?

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flyskyposted 4 years agoin reply to this

Possibly can be, but note the number 1 as a hint...

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john000posted 4 years agoin reply to this

Fibonacci numbers

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flyskyposted 4 years agoin reply to this

...close :-) So, on the green fields we have numbers: 2,3,5,7,11,13,...

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john000posted 4 years agoin reply to this

Prime #'s. Seems to be a spiral of numbers - so 17,19,23

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flyskyposted 4 years agoin reply to this

Yes! It is the spiral of prime numbers. It was discovered by the mathematician Stanislav Ulam in 1963 so it is called the Ulam spiral. Spiral of a larger size with points representing primes is beautiful.

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john000posted 4 years agoin reply to this

Great puzzle. Thank you.

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flyskyposted 4 years agoin reply to this

...welcome :-)

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flyskyposted 4 years ago

Hint: Imagine the rest of natural numbers, starting with number 1, on the figure: number 2 is on the square right next to the number 1, number 3 is one square above the number 2, number 4 is left next to the number 3 (i.e. one square above the number 1),... number 6 is down next to the number 5 (i.e. left next to the number 1), etc.

Which type of numbers fall on green squares?

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