My (incomplete) grid of all presidents (since 1894) who have met each other (Read description)

The sheet above shows which presidents have met each other.

In green are the connections that could prove via photographs.

In blue is a connection that is agreed to have taken place, but without photographic evidence (This will be more important when I go into the 1800s and 1700s later).

In yellow are the connections I couldn’t prove, but believe could have taken place. I want to see if any one of you could help me find out.

In tan are the blank spaces, ones are the possible, but logic points to no.

In dark red are impossible connections. Those two president’s lives did not overlap.

Are there any connections you are aware of I can confirm with a source, preferably with photographic evidence?

I’ll also take any photos or sources for presidents before this time frame, as I am going to do a complete graph eventually.

Thanks in advance!

The sheet above shows which presidents have met each other.

In green are the connections that could prove via photographs.

In blue is a connection that is agreed to have taken place, but without photographic evidence (This will be more important when I go into the 1800s and 1700s later).

In yellow are the connections I couldn’t prove, but believe could have taken place. I want to see if any one of you could help me find out.

In tan are the blank spaces, ones are the possible, but logic points to no.

In dark red are impossible connections. Those two president’s lives did not overlap.

Are there any connections you are aware of I can confirm with a source, preferably with photographic evidence?

I’ll also take any photos or sources for presidents before this time frame, as I am going to do a complete graph eventually.

Thanks in advance!