OFFSET
1,1
LINKS
Harry J. Smith, Table of n, a(n) for n = 1..45
EXAMPLE
Prime 93836531 reversed base 10 = 13563839, a prime.
93836531 = 215511462 base 9, reversed = 264115512 base 9 = 116986691, a prime.
93836531 = 545752363 base 8, reversed = 363257545 base 8 = 63790949, a prime.
93836531 = 2216411615 base 7, reversed = 5161146122 base 7 = 212620277, a prime.
93836531 = 13151124215 base 6, reversed = 51242115131 base 6 = 316991071, a prime.
93836531 = 143010232111 base 5, reversed = 111232010341 base 5 = 61594471, a prime.
93836531 = 11211331103303 base 4, reversed = 30330113311211 base 4 = 217152869, a prime.
93836531 = 20112120101112002 base 3, reversed = 20021110102121102 base 3 = 90058187, a prime.
93836531 = 101100101111101010011110011 base 2, reversed = 110011110010101111101001101 base 2 = 108617549, a prime.
PROG
(PARI) emirp(p, b)=my(q, t=p); while(t, q=b*q+t%b; t\=b); isprime(q) && p!=q
is(n)=for(b=2, 10, if(!emirp(n, b), return(0))); isprime(n) \\ Charles R Greathouse IV, Sep 03 2013
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Harry J. Smith, Jan 15 2008
STATUS
approved