<p>In the integer 3589 the digest are all different and increase from left to right. How many integers between 4,000 and 5,000 have digits that are all different and that increase from left to right?</p>
<p>How would I get to the answer (10)</p>
<p>4567
4568
4569
4578
4589
4579
4678
4679
4689
4789</p>
<p>^ yeahhh</p>
<p>theres probably some ridiculous way to get it using sequences/series/whatever but for these questions its sometimes easier to just list them…</p>
<p>^^
no there isnt, you MUST list them.</p>