What is wrong with this button?

Recently I was going through my memory box and I came across this button. It was given out by the hundreds at a conference in the 1970s. . What is the spirit of 100110 you ask? That represents the number 38 which doesn’t seem to mean much. And it really doesn’t because that is not the number that was supposed to be there. Who ever was in charge of printing the buttons left off a zero where the…