Successive prime differences: Difference between revisions

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 =={{header|Perl 6}}==
+===Categorized by Successive===
 {{works with|Rakudo|2019.03}}
 Essentially the code from the [[Sexy_primes#Perl_6|Sexy primes]] task with minor tweaks.
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       Count: 306
 </pre>
+===Precomputed Differences===
+{{works with|Rakudo|2019.03}}
+<lang perl6>use Math::Primesieve;
+constant $max    = 1_000_000;
+constant @primes = Math::Primesieve.primes($max);
+constant @diffs  = @primes.skip Z- @primes;
+say "Given all ordered primes <= $max, sets with successive differences of:";
+for (2,), (1,), (2,2), (2,4), (4,2), (6,4,2) -> @succ {
+    my $size = @succ.elems;
+    my @group_start_offsets = @diffs.rotor( $size => 1-$size )
+                                    .grep(:k, { $_ eqv @succ });
+    my ($first, $last) = @group_start_offsets[0, *-1]
+                         .map: { @primes.skip($_).head($size + 1) };
+    say sprintf '%10s has %5d sets: %15s … %s',
+        @succ.gist, @group_start_offsets.elems, $first, $last;
+}</lang>
+{{Out}}
+<pre>Given all ordered primes <= 1000000, sets with successive differences of:
+       (2) has  8169 sets:             3 5 … 999959 999961
+       (1) has     1 sets:             2 3 … 2 3
+     (2 2) has     1 sets:           3 5 7 … 3 5 7
+     (2 4) has  1393 sets:          5 7 11 … 999431 999433 999437
+     (4 2) has  1444 sets:         7 11 13 … 997807 997811 997813
+   (6 4 2) has   306 sets:     31 37 41 43 … 997141 997147 997151 997153</pre>
 =={{header|Python}}==