Palindromic primes in base 16: Difference between revisions
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for n = 1 to limit |
for n = 1 to limit |
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hex = |
hex = hex(n) |
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if ispalindrome(hex) and isprime(n) |
if ispalindrome(hex) and isprime(n) |
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see "" + hex + " " |
see "" + upper(hex) + " " |
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row = row + 1 |
row = row + 1 |
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if row%5 = 0 |
if row%5 = 0 |
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see nl + "Found " + row + " palindromic primes in base 16" + nl |
see nl + "Found " + row + " palindromic primes in base 16" + nl |
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see "done..." + nl |
see "done..." + nl |
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func decimaltobase(nr,base) |
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binList = [] |
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binary = 0 |
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remainder = 1 |
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while(nr != 0) |
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remainder = nr % base |
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ind = find(decList,remainder) |
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rem = baseList[ind] |
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add(binList,rem) |
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nr = floor(nr/base) |
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end |
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binlist = reverse(binList) |
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binList = list2str(binList) |
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binList = substr(binList,nl,"") |
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return binList |
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</lang> |
</lang> |
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{{out}} |
{{out}} |
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Revision as of 13:44, 23 June 2021
Palindromic primes in base 16 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
- Find palindromic primes in base 16, where n < 500
Ring
<lang ring> load "stdlib.ring" see "working..." + nl see "Palindromic primes in base 16:" + nl row = 0 decList = 0:15 baseList = ["0","1","2","3","4","5","6","7","8","9","A","B","C","D","E","F"] limit = 500
for n = 1 to limit
hex = hex(n)
if ispalindrome(hex) and isprime(n)
see "" + upper(hex) + " "
row = row + 1
if row%5 = 0
see nl
ok
ok
next
see nl + "Found " + row + " palindromic primes in base 16" + nl see "done..." + nl </lang>
- Output:
working... Palindromic primes in base 16: 2 3 5 7 B D 11 101 151 161 191 1B1 1C1 Found 13 palindromic primes in base 16 done...