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A136634 Primes whose reversals in bases 10, 9, 8, 7, 6, 5, 4, 3 and 2 are all prime. 2
93836531, 1819395637, 1919723027, 1963209431, 3277373311, 3540866053, 15969326033, 16075946743, 16735166477, 17145519379, 71606465171, 71624919101, 72338598089, 73544885809, 73939267019, 74592559721 (list; graph; refs; listen; history; text; internal format)
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

Cf. A007500, A074832, A136186, A136187.

Sequence in context: A117624 A147527 A293244 * A033625 A128673 A028502

Adjacent sequences:  A136631 A136632 A136633 * A136635 A136636 A136637

KEYWORD

base,nonn

AUTHOR

Harry J. Smith, Jan 15 2008

STATUS

approved

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Last modified December 7 09:33 EST 2019. Contains 329843 sequences. (Running on oeis4.)