Odd squarefree semiprimes: Difference between revisions
Content added Content deleted
(→{{header|ALGOL 68}}: Calculate a more sensible number of primes) |
m (C# - Edited code & output to reflect new task name) |
||
Line 63: | Line 63: | ||
=={{header|C#|CSharp}}== |
=={{header|C#|CSharp}}== |
||
This reveals a set of |
This reveals a set of semi-prime numbers (with exactly two factors for each '''<big>''n''</big>'''), where '''<big>''1 < p < q < n''</big>'''. It is square-free, since '''<big>''p < q''</big>'''. |
||
<lang csharp>using System; using static System.Console; using System.Collections; |
<lang csharp>using System; using static System.Console; using System.Collections; |
||
using System.Linq; using System.Collections.Generic; |
using System.Linq; using System.Collections.Generic; |
||
Line 73: | Line 73: | ||
res.Add(amt = pr[p] * pr[q]); } res.Sort(); foreach(var item in res.TakeWhile(x => x < lmt)) |
res.Add(amt = pr[p] * pr[q]); } res.Sort(); foreach(var item in res.TakeWhile(x => x < lmt)) |
||
Write("{0,4} {1}", item, ++c % 20 == 0 ? "\n" : ""); |
Write("{0,4} {1}", item, ++c % 20 == 0 ? "\n" : ""); |
||
Write("\n\nCounted {0} |
Write("\n\nCounted {0} odd squarefree semiprimes under {1}", c, lmt); } } |
||
class PG { public static IEnumerable<int> Primes(int lim) { |
class PG { public static IEnumerable<int> Primes(int lim) { |
||
Line 93: | Line 93: | ||
933 939 943 949 951 955 959 965 973 979 985 989 993 995 |
933 939 943 949 951 955 959 965 973 979 985 989 993 995 |
||
Counted 194 |
Counted 194 odd squarefree semiprimes under 1000</pre> |
||
=={{header|C++}}== |
=={{header|C++}}== |