Talk:ALGOL 68-primes: Difference between revisions
Content added Content deleted
(→Source code: Added PROC is probably prime) |
(→ALGOL_68-primes Source code: Added APPROXIMATESOEVESIZEFPR operator based on Chebyshev's pi(n)/(n/ln(n)) ~ 1 as n approaches infinity) |
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is prime |
is prime |
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FI # is probably prime # ; |
FI # is probably prime # ; |
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# returns an approximate size of sieve required for n primes # |
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# uses Chebyshev's formula of n/ln(n), increased by 20% # |
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# as n/ln(n) is only pi(n) when n appraoches infinity # |
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OP APPROXIMATESIEVESIZEFOR = ( INT n )INT: |
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BEGIN |
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INT result := 10; |
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WHILE INT primes = ENTIER ( ( result / ln( result ) ) * 1.2 ); |
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primes < n |
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DO |
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result *:= 4 |
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OD; |
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result |
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END # APPROXIMATESIEVESIZEFOR # ; |
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# END primes.incl.a68 #</lang> |
# END primes.incl.a68 #</lang> |