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A092529
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Primes p such that both the digit sum of p plus p and the digit product of p plus p are also primes.
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1
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163, 233, 293, 431, 499, 563, 617, 743, 1423, 1483, 1489, 1867, 2273, 2543, 2633, 3449, 4211, 4217, 4273, 4547, 4729, 5861, 6121, 6529, 6637, 6653, 6761, 6857, 6949, 7681, 8273, 8431, 8837, 8839, 9649, 9689
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OFFSET
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1,1
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COMMENTS
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Zeros are not permitted in p; thus, for example, 101 is not included. - Harvey P. Dale, May 25 2013
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LINKS
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EXAMPLE
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a(2) = 233: 233+(2+3+3) = 233+8 = 241, which is prime. 233+(2*3*3) = 233+18 = 251, which is prime.
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MAPLE
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filter:= proc(p) local L;
if not isprime(p) then return false fi;
L:= convert(p, base, 10);
if member(0, L) then return false fi;
isprime(p + convert(L, `+`)) and isprime(p + convert(L, `*`))
end proc:
select(filter, [seq(i, i=3..10000, 2)]); # Robert Israel, Feb 20 2024
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MATHEMATICA
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pppQ[n_]:=Module[{idn=IntegerDigits[n]}, !MemberQ[idn, 0]&&And@@PrimeQ[ {n+ Total[idn], n+Times@@idn}]]; Select[Prime[Range[1200]], pppQ] (* Harvey P. Dale, May 25 2013 *)
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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