I read an article a month or so ago but I can't find it now. I was expecting it to talk about the cycles being prime numbers but instead it described the cicada

I read an article a month or so ago but I can't find it now. I was expecting it to talk about the cycles being prime numbers but instead it described the cicada's cycle in terms of 1 year + 3 or 4 cycles of 4 years. Same phenomenon but just a different way of thinking about it.