The Four Power Days

Today, May 5 is written 5/12 in the US and 512 is a power of 2, it's $2^9$. I tweeted that and received a rapid reply from Peter Inglesby that in UK-style dates it's 12/5 which is 125 which is $5^3$. Which made me wonder whether there were other dates that had the same property in the US and UK on the same day.

Peter wrote a quick script:
and determined that there are four such dates:

March 24: US 3/24; $324 = 18^2$. UK 24/3; $243 = 3^5$

May 12: US 5/12; $512 = 2^9$. UK 12/5; $125 = 5^3$

June 25: US 6/25; $625 = 5^4$. UK 25/6; $256 = 2^8$

December 5: US 12/5; $125 = 5^3$. UK 5/12. $512 = 2^9$

Now I just need to think up a mystical significance to this, start a religion and retire on the proceeds.

Comments

Unknown said…

I like Python, but the shell, in this case bash, can answer it too.

seq 0 365 | xargs -I_ date -d '2012-01-01 + _ days' +'%-m%-d %-d%-m' |
sed "$(echo {1,{2..55}}' '{2,{3..11}}^pc | dc | awk '$0 >= 11 && $0 <= 3112' | sort -nu | sed 's#.*#/\\<&\\>/s/$/+/;#')" |
sed -n 's/++$//p'

10:10 AM

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