## Happy New Year 2019

Posted: January 1, 2019 in Mathematics

I was in bed last night thinking about the number 2019. Obviously it is not a prime. Can I find a way to add up the numbers 1 to 9 (in the exact order) to get 2019? First of all, 2019 is divisible by 3. it’s a product of 3 and 673. So I can do this, 2019 = (1 + 2)(673).

It isn’t difficult to verify 673 a prime number. Now I have used the digits 1 and 2 and there are 7 left, they are 3, 4, 5, 6, 7, 8, 9. After a while of trying out different products, I can’t find 673 out of the remaining digits. So I try factorials and I found 6! = 720 is pretty close to 673, a difference of only 47. And 4 times 5 is 20 so I have 27 left to consider, which is great coz I know 7 + 8 + 9 = 3 times 8 which is 24 and with the remaining digit 3 I am done! $(1+2)\times(-3-4\times5+6!-7-8-9)=2019$

HAPPY NEW YEAR !!!

Remark

Matt Parker has a YouTube video on 2019 and I think it is amazing that $0^3+1^8+2^7-3^9+4^6+5^4+6^2+7^5+8^1+9^0=2019$

and here is the video

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