Find 7 Digit Prime palindrome in Pi

7 Digit Pi lindrome

pi <- read.csv("./pi.csv", header=FALSE, sep=" ")                                                                                                                         
dig <- 14000                                                                                                                                                              
pistr <- paste(c(pi[1,]$V2, ".", head(pi[-1,], dig-1)$V2), collapse="")                                                                                                   
is.palindrome <- function (word) { identical(word, paste(rev(strsplit(word, "")[[1]]), collapse="")) }                                                                    
is.prime <- function(n) n == 2L || all(n %% 2L:floor(sqrt(n)) != 0)                                                                                                       
base <- 1                                                                                                                                                                 
end <- 7                                                                                                                                                                  
repeat {                                                                                                                                                                  
  if (is.palindrome(substr(pistr, base, end)) & is.prime(as.numeric(substr(pistr, base, end)))) {                                                                         
    print(substr(pistr, base, end))                                                                                                                                       
    break                                                                                                                                                                 
  }                                                                                                                                                                       
  base <- base + 1                                                                                                                                                        
  end <- end + 1                                                                                                                                                          
}                                                                                                                                               

pi.txt

http://oeis.org/A000796/b000796.txt

nathanjohnson320@vm-2:~$ time Rscript pi.R
[1] "9149419"

real 0m3.155s
user 0m3.055s
sys 0m0.075s