I am still not sure I understand your specification. You should test this code with more data to see whether it behaves well in all the border cases: 
#!/usr/bin/perl
use warnings;
use strict;

my ($first, $last, $last_small) = ('0e0', 0, 0);
while (<DATA>) {
    my ($big, $small) = split;
    next if 4 >= $small;
    if ($big > $first + 50) {
        show($first, $last, $last_small);
        $first = $big;
    }
    $last       = $big;
    $last_small = $small;
}
show($first, $last, $last_small);

sub show {
    my ($first, $last, $last_small) = @_;
    print "$first ", $last + 50, " $last_small\n" unless '0e0' eq $fir
+st;
}

__DATA__
109026 3
109027 28
109028 30
116958 15
116960 35
116961 39
116962 70
116963 72
147184 2
147588 1
153087 32

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لսႽ† ᥲᥒ⚪⟊Ⴙᘓᖇ Ꮅᘓᖇ⎱ Ⴙᥲ𝇋ƙᘓᖇ

In reply to Re: Sorting the numbers: A little tricky. by choroba
in thread Sorting the numbers: A little tricky. by oxydeepu

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