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A276169
Primes that remain primes after adding to them their largest missing digit.
1
2, 29, 59, 149, 191, 269, 359, 449, 479, 491, 569, 593, 599, 719, 911, 929, 1109, 1193, 1229, 1319, 1439, 1559, 1619, 1979, 1987, 2129, 2339, 2459, 2549, 2609, 2699, 2897, 2909, 2963, 3209, 3299, 3449, 3491, 3539, 3719, 3911, 3923, 4019, 4049, 4091, 4349, 4649, 4793, 4943, 4987, 5099, 5399, 5519, 5639, 5693, 5897
OFFSET
1,1
COMMENTS
Resulting primes are: 11, 37, 67, 157, 199, 277, 367, 457, 487, 499, 577, 601, 607, 727, 919, 937, 1117, 1201, 1237, 1327, 1447, 1567, 1627, 1987, 1993, 2137.
If n > 2, the largest missing digit must be even, so in particular n contains digit 9. - Robert Israel, Sep 01 2016
Pandigital primes not included. - Zak Seidov, Sep 02 2016
LINKS
EXAMPLE
2+9=11, 29+8=37, 59+8=67 all primes.
MAPLE
lmd:= n -> max({$1..9} minus convert(convert(n, base, 10), set)):
select(t -> isprime(t) and isprime(t + lmd(t)), [2, seq(i, i=3..10000, 2)]); # Robert Israel, Sep 01 2016
MATHEMATICA
Select[Prime[Range[1000]], PrimeQ[#+Complement[Range[9], IntegerDigits[#]][[-1]]]&]
PROG
(PARI) is(n) = {my(s); if(isprime(n), s = setminus(s=Set(vector(9, i, i)), Set(digits(n))); if(#s>0, n+=s[#s], return(0)); return(isprime(n)))} \\ David A. Corneth, Aug 23 2016
CROSSREFS
Cf. A116667 (largest missing digit).
Sequence in context: A142969 A281546 A115448 * A107161 A372932 A041097
KEYWORD
nonn,base
AUTHOR
Zak Seidov and Eric Angelini, Aug 22 2016
STATUS
approved