My BIL who was a Marine, and later a Boy scout leader, taught me that a hangman’s noose should have 13 loops. Looks like the one pictured is missing 4.
I was thinking the same about 13:
The number thirteen was thought to be unlucky. Consequently, in myth, if not in actual practice, thirteen coils were found in ahangman’s noose, a foreboding sign for those convicted to be hanged.
Woody Guthrie sings of the hangman using thirteen coils:
Did you ever see a hangman tie a hangknot?
I’ve seen it many a time and he winds, he winds,
After thirteen times he’s got a hangknot.
https://en.wikipedia.org/wiki/Hangman%27s_knot