Problem 44341. Hexagonal numbers on a spiral matrix

Created by Mehmet OZC

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Last Solution submitted on Nov 30, 2020

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Solution 1330565

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Angelo Gelmini on 7 Nov 2017

I am not able to figure out why the solutions of my code to test 8 and 9 are wrong.
My wrong results:
- test 8 -> '1250000041666667776'
- test 9 -> '13107200170666672128'

Heiko on 15 Nov 2017

I get precisely the same results as Angelo...

Mehmet OZC on 16 Nov 2017

Angelo and Heiko, your solutions are working to a degree. However to obtain exact results on big numbers you have to use different tools. You can search for uint64 and bigdecimal. Hope it helps.

Hans Kramer on 3 Dec 2018

Thanks for the tip with uint64.

Solution 1305838

2 Comments

2 Comments

Mehmet OZC on 21 Oct 2017

First line is adopted from James's solution: https://www.mathworks.com/matlabcentral/cody/problems/2455-diagonal-of-a-spiral-matrix/solutions/1239477

James on 2 Nov 2017

I was just happy I could use "diag" and "spiral" in this problem, but it's always nice to see some of my solutions get used in other code.

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Problem 44341. Hexagonal numbers on a spiral matrix

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Problem 44341. Hexagonal numbers on a spiral matrix

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