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King's Maths School

Challenge 458: Triskaphobia

I'm good at counting with certain constraints!

I have a serious fear of a certain digit which I don't want to name. A mathematician could discover this digit by spotting that I have used no words with letters equal to a multiple of this digit, other than this problem's title, ironically.

When I count, I skip anything where this digit appears. I also skip anything that is a multiple of this digit.

Suppose I start counting from 1. When I have counted a hundred numbers, what is the last of those numbers?

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