PLEASE HELP :( :( I'd really appreciate it!!

Conundrum Lenny went for a walk down a dirt path toward Meri Acres Farm. Almost immediately after he started walking, he saw a number written in the dirt: "84".

A few feet later, he saw a second number: "134".

Then another: "218".

As he continued to walk, he came across even more numbers: 296, 380, 429, 468, 551, 635, 684, 734, 788, 868, and 984.

He decided to keep walking. It turns out, there were a total of exactly four hundred numbers written in the dirt. A couple of them were repeated numbers, but most of them were unique.

What was the 40

Question

PLEASE HELP :( :( I'd really appreciate it!!

Conundrum Lenny went for a walk down a dirt path toward Meri Acres Farm. Almost immediately after he started walking, he saw a number written in the dirt: "84".

A few feet later, he saw a second number: "134".

Then another: "218".

As he continued to walk, he came across even more numbers: 296, 380, 429, 468, 551, 635, 684, 734, 788, 868, and 984.

He decided to keep walking. It turns out, there were a total of exactly four hundred numbers written in the dirt. A couple of them were repeated numbers, but most of them were unique.

What was the 40