Ormiston pairs: Difference between revisions
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326,926 Ormiston pairs before 1,000,000,000
</pre>
=={{header|Haskell}}==
<syntaxhighlight lang=haskell>import Data.List (sort)
import Data.Numbers.Primes (primes)
---------------------- ORMISTON PAIRS --------------------
ormistonPairs :: [(Int, Int)]
ormistonPairs =
[ (fst a, fst b)
| (a, b) <- zip primeDigits (tail primeDigits),
snd a == snd b
]
primeDigits :: [(Int, String)]
primeDigits = (,) <*> (sort . show) <$> primes
--------------------------- TEST -------------------------
main :: IO ()
main =
putStrLn "First 30 Ormiston pairs:"
>> mapM_ print (take 30 ormistonPairs)
>> putStrLn "\nCount of Ormistons up to 1,000,000:"
>> print (length (takeWhile ((<= 1000000) . snd) ormistonPairs))</syntaxhighlight>
{{Out}}
<pre>First 30 Ormiston pairs:
(1913,1931)
(18379,18397)
(19013,19031)
(25013,25031)
(34613,34631)
(35617,35671)
(35879,35897)
(36979,36997)
(37379,37397)
(37813,37831)
(40013,40031)
(40213,40231)
(40639,40693)
(45613,45631)
(48091,48109)
(49279,49297)
(51613,51631)
(55313,55331)
(56179,56197)
(56713,56731)
(58613,58631)
(63079,63097)
(63179,63197)
(64091,64109)
(65479,65497)
(66413,66431)
(74779,74797)
(75913,75931)
(76213,76231)
(76579,76597)
Count of Ormistons up to 1,000,000:
382</pre>
=={{header|J}}==
Line 824 ⟶ 885:
+/isorm i.&.(p:inv) 1e7 NB. number of Ormiston pairs less than 1e7
3722</syntaxhighlight>
=={{header|jq}}==
{{works with|jq}}
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