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# Subtractive generator

```perl
sub bentley-clever($seed) {
    constant $mod = 1_000_000_000;
    my @seeds = ($seed % $mod, 1, (* - *) % $mod ... *)[^55];
    my @state = @seeds[ 34, (* + 34 ) % 55 ... 0 ];

    sub subrand() {
        push @state, (my $x = (@state.shift - @state[*-24]) % $mod);
        $x;
    }

    subrand for 55 .. 219;

    &subrand ... *;
}

my @sr = bentley-clever(292929);
.say for @sr[^10];
```

Here we just make the seeder return the random sequence as a lazy list.

```
467478574
512932792
539453717
20349702
615542081
378707948
933204586
824858649
506003769
380969305
```