In mathematics, the Perkel graph, named after Manley Perkel, is a 6-regular graph with 57 vertices and 171 edges. It is the unique distance-regular graph with intersection array (6, 5, 2; 1, 1, 3). The Perkel graph is also distance-transitive, and it’s the skeleton of an abstract regular polytope, the 57-cell.
Okay so we were in math class today getting homework on parabolas (curvy line graphs) and the math teacher wanted to be very clear that we weren’t supposed to put all our lines on the same graph.
To enforce the point, she says “I don’t want you guys drawing your parabolas on top of each other! No sexy parabolas!”
The class died laughing. And she just stood there looking at her notes for a moment and said “Did I actually say that out loud? I always think that in my head but I never say it!” So she burst out laughing too.
But hands down the best part was when my friend turned to me and said “Parabolas have great curves though.”
(I swear I never felt like more of a math geek then when I was laughing at that joke).
The graph reveals a striking pattern. After adjusting for inflation, income was basically flat for households in the bottom half of the economic ladder. Right around the middle, income starts to pick up — and the higher you go up the income ladder, the more income growth you see.