Check if sum of first n primes is prime: Difference between revisions

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see "working..." + nl
see "working..." + nl
see "Sum of first primes is prime:" + nl
see "Sum of first primes is prime:" + nl
n = 0
num = 0
num = 0
primSum = 0
primSum = 0


while true
for n = 1 to 10000
n++
if isprime(n)
if isprime(n)
primSum += n
primSum += n
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exit
exit
ok
ok
end
next


see "done..." + nl
see "done..." + nl

Revision as of 08:24, 23 July 2021

Check if sum of first n primes is prime is a draft programming task. It is not yet considered ready to be promoted as a complete task, for reasons that should be found in its talk page.
Task
Check if sum of first n primes is prime, where n <= 20



Ring

<lang ring> load "stdlib.ring" see "working..." + nl see "Sum of first primes is prime:" + nl n = 0 num = 0 primSum = 0

while true

   n++
   if isprime(n)
      primSum += n
      if isprime(primSum)
         num++
         see "n" + "(" + num + ") = " + primsum + " is prime" + nl
      ok
   ok
   if num = 20
      exit
   ok

end

see "done..." + nl </lang>

Output:
working...
Sum of first primes is prime:
n(1) = 2 is prime
n(2) = 5 is prime
n(3) = 17 is prime
n(4) = 41 is prime
n(5) = 197 is prime
n(6) = 281 is prime
n(7) = 7699 is prime
n(8) = 8893 is prime
n(9) = 22039 is prime
n(10) = 24133 is prime
n(11) = 25237 is prime
n(12) = 28697 is prime
n(13) = 32353 is prime
n(14) = 37561 is prime
n(15) = 38921 is prime
n(16) = 43201 is prime
n(17) = 44683 is prime
n(18) = 55837 is prime
n(19) = 61027 is prime
n(20) = 66463 is prime
done...