In Eastern European folklore, many vampires suffered from OCD, specifically having strong compulsions to count. Bags of rice or seed were often placed at graves to occupy them at night by counting the grains. This was the inspiration for Sesame Street’s Count Von Count. – WTF Fun Facts
Source: Vampires Traits – Vampires – Dracula
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This isn’t true, myself being from Transilvania itself, the truth is some people still believe in “ghouls” and evil spirits (not vampires) especially in rural areas, and they hang garlic cloves around their windows all year round, but this story about rice and counting is pure made up bs.
This is an interesting fact, but the linked article doesn’t say Count von Count was inspired by this folklore, just that he’s an example that is consistent with it. It’s much more likely that it’s a convenient coincidence and the inspiration for the character was simply that vampires are often portrayed as Counts and a “Count” fit well with teaching about counting numbers.