Monday, April 29, 2019

mathematics - Prime to Prime: Get all first 25 Prime Numbers using up to 4 Primes



The first 25 Prime Numbers are



2,3,5,7,11,13,17,19,23,29,31,37,41,43,47,53,59,61,67,71,73,79,83,89,97



Using up to 4 prime numbers and the following mathematical operations, get all the 25 primes.



+ - x / ^ √ !



No other operators (like !!) are allowed.


Other rules




  • You cannot use same Prime Number more than once.

  • You can use only Prime Numbers.

  • Any number that appears as a number in the equation will be counted as one of the primes out of four (e.g. 7^2 means you have used both 7 and 2).

  • You do not have to use all the 4 primes in every equation.

  • You must use the SAME 4 primes in every equation. If you select say 2, 13, 17, 23 then they are the only primes that to appear in every equation to get the 25 primes.


I have 1 solution. There may be more.


No programming please.
NO PARTIAL ANSWERS.




Answer



Using 2,3,7,11:



2=2


3=3


5=11+372


7=7


11=11


13=2+11


17=3!+11



19=23+11


23=37+2


29=(72)!311


31=3112


37=(113!)7+2


41=72+311


43=211+37


47=311+27


53=23!11


59=3!117



61=(112)3!+7


67=723+11


71=23!+7


73=3!11+7


79=711+2


83=711+3!


89=711+23!


97=(2+11)7+3!



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