#!/usr/bin/perl

# https://perlmonks.org/?node_id=1227147

use warnings;
use strict;

my $pattern = 'FTTF';
my $repeated_pattern = $pattern x ( 1 + ( map $_, 0 .. 12 ) / length $pattern );

my @result = grep { $repeated_pattern =~ /./g; $& eq 'T' } 0 .. 12;

print $repeated_pattern, "\n";
print "@result\n";