Check if sum of first n primes is prime: Difference between revisions
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{{Draft task}} |
{{Draft task}} |
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;Task:Check if sum of first '''n''' primes is prime, where '''n < |
;Task:Check if sum of first '''n''' primes is prime, where '''n <= 20''' |
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<br><br> |
<br><br> |
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load "stdlib.ring" |
load "stdlib.ring" |
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see "working..." + nl |
see "working..." + nl |
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see "Sum of first |
see "Sum of first primes is prime:" + nl |
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num = 0 |
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primSum = 0 |
primSum = 0 |
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for n = 1 to |
for n = 1 to 10000 |
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if isprime(n) |
if isprime(n) |
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primSum += n |
primSum += n |
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if isprime(primSum) |
if isprime(primSum) |
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num++ |
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see "n" + "(" + |
see "n" + "(" + num + ") = " + primsum + " is prime" + nl |
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ok |
ok |
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ok |
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if num = 20 |
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exit |
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ok |
ok |
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next |
next |
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working... |
working... |
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Sum of first primes is prime: |
Sum of first primes is prime: |
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n( |
n(1) = 2 is prime |
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n( |
n(2) = 5 is prime |
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n( |
n(3) = 17 is prime |
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n( |
n(4) = 41 is prime |
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n( |
n(5) = 197 is prime |
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n( |
n(6) = 281 is prime |
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n( |
n(7) = 7699 is prime |
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n( |
n(8) = 8893 is prime |
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n( |
n(9) = 22039 is prime |
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n( |
n(10) = 24133 is prime |
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n( |
n(11) = 25237 is prime |
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n( |
n(12) = 28697 is prime |
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n( |
n(13) = 32353 is prime |
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n( |
n(14) = 37561 is prime |
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n( |
n(15) = 38921 is prime |
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n( |
n(16) = 43201 is prime |
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n( |
n(17) = 44683 is prime |
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n( |
n(18) = 55837 is prime |
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n( |
n(19) = 61027 is prime |
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n( |
n(20) = 66463 is prime |
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n(953) = 70241 is prime |
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done... |
done... |
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</pre> |
</pre> |
Revision as of 07:36, 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 num = 0 primSum = 0
for n = 1 to 10000
if isprime(n) primSum += n if isprime(primSum) num++ see "n" + "(" + num + ") = " + primsum + " is prime" + nl ok ok if num = 20 exit ok
next
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...