import arcpy

for i in range(100):
    print i
    arcpy.CreateRandomPoints_management("c:/data/project", "samplepoints", "c:/data/studyarea.shp", "", 500, "", "POINT", "")

library(sp)
data(meuse)
coordinates(meuse) <- ~x+y

dmat <- spDists(meuse)

min.dist <- 500
dmat[dmat <= min.dist] <- NA

samples <- data.frame(ID=rownames(meuse@data), kNN=NA)
  for(i in 1:nrow(dmat) ) {
    x <- as.vector( dmat[,i] )
      names(x) <- samples$ID
    x <- x[!is.na(x)]
    if(!length(x) == 0) {
      samples[i,][2] <- names(x)[sample(1:length(x), 1)]
      } else {
      samples[i,][2] <- NA
    }
  }

meuse@data <- data.frame(meuse@data, kNN=samples$kNN)
  head(meuse@data)

meuse.sub <- meuse[which(rownames(meuse@data) %in% unique(samples$kNN)),]