Semiprime: Difference between revisions

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 {{works with|jq}}
 '''Works with gojq, the Go implementation of jq'''
-See e.g. [[Erd%C5%91s-primes#jq]] for a suitable implementation of `is_prime`.
 <syntaxhighlight lang="jq">
-# Output: a stream of proper factors (probably unsorted)
-def proper_factors:
-  range(2; 1 + sqrt|floor) as $i
-  | if (. % $i) == 0
-    then (. / $i) as $r
-    | if $i == $r then $i else $i, $r end
-    else empty
-    end;
 def is_semiprime:
-  . as $n
+  {i: 2, n: ., nf: 0}
+  | until( .i > .n or .result;
-  | any(proper_factors;
-        is_prime and (($n / .) | (. == $n or is_prime) );
+      until(.n % .i != 0 or .result;
+        if .nf == 2 then .result = 0
+        else .nf += 1
+        | .n /= .i
+        end)
+      | .i += 1)
+  | if .result == 0 then false else .nf == 2 end;
 </syntaxhighlight>
 '''Examples'''