I think it's a very safe assumption that, no, there isn't. I'm sure somebody somewhere at sometime (probably alot of people) has wrote an algorithm to check. One or two might drop off now and again, but they get grabbed pretty quick.
Of course not! Seems you are n00b in domain biz!~
all LLL.com,.org,.net,.biz,.us,.info are regged
as all NNN.com,.org,.net,.biz,.us,.infoand all the NNNN.com,.net