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 A088092 Palindromic primes p such that if each digit d is replaced by 10-d then the resulting palindrome is also a prime. 1
 3, 5, 7, 181, 191, 313, 353, 383, 727, 757, 797, 919, 929, 12421, 12721, 14341, 17971, 32323, 78787, 93139, 96769, 98389, 98689, 1129211, 1145411, 1153511, 1175711, 1178711, 1183811, 1221221, 1273721, 1328231, 1486841, 1633361, 1824281 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Digit 0 is not allowed. - Robert Israel, Sep 14 2020 LINKS Robert Israel, Table of n, a(n) for n = 1..10000 EXAMPLE 181 is a member as replacing 1 by 10-1 = 9 and 8 by 10-8 =2 gives 929 which is also a prime. MAPLE R:= NULL: count:= 0: for d from 1 by 2 while count < 100 do   m:= ceil(d/2);   for r from 0 to 9^m-1 do     L:= convert(9^m+r, base, 9)[1..m] + [1\$m];     L:= [ seq(L[-i], i=1..m-1), op(L)];     x:= add(L[i]*10^(i-1), i=1..d);     if isprime(x) and isprime((10^d-1)*10/9-x) then R:= R, x; count:= count+1       fi od od: R; # Robert Israel, Sep 14 2020 CROSSREFS Cf. A002385 (palindromic primes). Sequence in context: A128344 A259385 A114366 * A174271 A211678 A082756 Adjacent sequences:  A088089 A088090 A088091 * A088093 A088094 A088095 KEYWORD base,nonn AUTHOR Amarnath Murthy, Sep 23 2003 EXTENSIONS Corrected and extended by David Wasserman, Jul 18 2005 STATUS approved

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Last modified December 6 18:16 EST 2021. Contains 349567 sequences. (Running on oeis4.)