OFFSET
1,1
COMMENTS
Leading zeros are dropped.
Since these numbers are just digit permutations of the primes the sequence is obviously infinite. - Charles R Greathouse IV, Oct 20 2008
PROG
(PARI) swapn(n, d) = \ d is the digit position to swap { local(j, ln, x, s, y, y2, tmp); for(x=10^(d-1), 10^(d-1)+n, s = Str(x); ln = length(s); y = eval(Vec(s)); tmp=y[d]; y[d]=y[ln-d+1]; y[ln-d+1]=tmp; y2=0; for(j=1, ln, y2+=y[j]*10^(ln-j); ); if(isprime(y2), print1(x", ")) ) }
CROSSREFS
KEYWORD
easy,nonn,base
AUTHOR
Cino Hilliard, Nov 05 2005
STATUS
approved