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A136634
Primes whose reversals in bases 10, 9, 8, 7, 6, 5, 4, 3 and 2 are all prime.
5
93836531, 1819395637, 1919723027, 1963209431, 3277373311, 3540866053, 15969326033, 16075946743, 16735166477, 17145519379, 71606465171, 71624919101, 72338598089, 73544885809, 73939267019, 74592559721
OFFSET
1,1
LINKS
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