What is actually against calculating the valid permutations in advance? A try:

#!/usr/bin/env perl

use strict;
use warnings;
use Algorithm::Permute;
use feature qw(say);
use Data::Dump;

my $n = [ 1, 2, 3, 3, 3, 4, 8 ];
my $p = Algorithm::Permute->new($n, 7);

my $m3 = qr/(.)\1\1/;
my $m2 = qr/(.)\1/;
my @v;

while ( my @r = $p->next ) {
    my $s = pack( "(A*)*", @r );
    next if $s =~ /$m3/;
    next if $s =~ /$m2/;
    push( @v, $s );
}

dd \@v;

__END__

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«The Crux of the Biscuit is the Apostrophe»

In reply to Re: Algorithm RFC: fast (pseudo-)random shuffle with no repetition by karlgoethebier
in thread Algorithm RFC: fast (pseudo-)random shuffle with no repetition by Anonymous Monk

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