apple-touch-icon.png missing. 404 error. How do I add icons??

I’m getting lots of 404 errors for the Apple Touch icons missing from the Twenty Sixteen theme.

The error is for the apple-touch-icon.png and I don’t see them in the twenty sixteen theme anywhere or in wordpress itself. It seems various apple devices are looking for different size apple-touch icons and getting 404 errors instead.

Ahy help greatfully appreciated.

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