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When I did math competitions I remember getting the advice to know the prime factorization of the current year.
by madcaptenor 2y ago
When I did math competitions I remember getting the advice to know the prime factorization of the current year.
- dxbydt 2y ago45^2 = 2025 => must be the sum of first 45 odds => 1 + 3 + ... + 87+ 89 = 2025 while its not pythagorean, 40^2 + 20^2 + 5^2 = 2025. 877 is another bullcrap that has shown up on a bunch of these tests. 877 is a prime, and four times 877 is 3508 = sum of all the divisors of 2025. there's a bunch more i shared with them.