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A158328
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Lessers p1 of twin primes with prime sums of digits of p1 and p2.
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1
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3, 5, 41, 137, 191, 197, 227, 281, 311, 461, 599, 641, 821, 827, 881, 1031, 1091, 1277, 1301, 1451, 1721, 1871, 2027, 2081, 2087, 2111, 2267, 2591, 2711, 2801, 3167, 3251, 3257, 3299, 3527, 3581, 3671, 3851, 4001, 4157, 4241, 4337, 4421, 4481, 4517, 4799
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OFFSET
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1,1
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COMMENTS
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LINKS
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EXAMPLE
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a(3)=41 is in the sequence because 41, 41+2=43, 4+1=5 and 4+3=7 are primes.
a(4)=137 is in the sequence because 137, 137+2=139, 1+3+7=11 and 1+3+9=13 are primes.
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MAPLE
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sd:= n -> convert(convert(n, base, 10), `+`):
p:= 1: q:= 2: count:= 0: Res:= NULL:
while count < 100 do
if q = p+2 and isprime(sd(p)) and isprime(sd(q)) then
count:= count+1; Res:= Res, p
fi;
p:= q; q:= nextprime(q);
od:
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MATHEMATICA
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sd[n_]:=Plus@@IntegerDigits[n]; Select[Prime[Range[650]], And@@PrimeQ[{#+2, sd[#], sd[#+2]}] &] (* Jayanta Basu, 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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