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A332968
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Lesser of twin primes p, p+2 such that prime(p) and prime(p+2) are also twin primes.
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1
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3, 5, 11, 41, 461, 1031, 1619, 2309, 2789, 7877, 8219, 9929, 11117, 12071, 16067, 18251, 18911, 22091, 23909, 26681, 28751, 30467, 32531, 33809, 38747, 40847, 41201, 41609, 43397, 46769, 49169, 56711, 58907, 73061, 79631, 89069, 91457, 92957, 96179, 110567, 113327, 114641, 117989, 122399, 123491
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OFFSET
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1,1
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LINKS
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EXAMPLE
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a(3) = 11 is a member because it is the lesser of the twin prime pair (11,13), and prime(11) = 31 and prime(13) = 41 are both twin primes.
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MAPLE
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P:= select(isprime, [2, seq(i, i=3..2*10^5, 2)]):
nP:= nops(P):
T:= P[select(i-> P[i+1]=P[i]+2, [$1..nP-1])]:
TS:= select(`<=`, T, nP-3):
select(t -> (P[t]+2=P[t+1] or P[t]-2=P[t-1]) and (P[t+2]+2=P[t+3] or P[t+2]-2=P[t+1]), TS);
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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