A man walks into an Irish pub…

…sits down at the bar and orders a pint. A man in the corner of the bar stands up and yells "42!" The whole bar bursts into laughter. The man at the bar looks around in utter confusion. As the bar tender hands over the pint to the man, an old fellow sitting next to him screams out "61" and again the bar roars with laughter. Finally, the man at the bar asks the bartender about the numbers. The bartender says "The Irish, do this thing where we associate numbers with old Irish jokes. Go ahead yell a number out." So the man stands up and yells out, "147!" and with that the whole bar falls on the floor crying laughing. People are rolling around and some can't even breathe. In absolute disbelief the man asks, "Okay, what the hell was so funny about that one?" The bartender wipes away his tears and says, "We haven't heard that one before!"