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A340570
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Averages k of twin prime pairs such that A075255(k) is also the average of a twin prime pair.
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1
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42, 72, 348, 1998, 4722, 9282, 28182, 34128, 34962, 46818, 46830, 57348, 59442, 71328, 79398, 81552, 97860, 113160, 115602, 117618, 138798, 151008, 157218, 158748, 179898, 183510, 184902, 185070, 234810, 244158, 245418, 284130, 316698, 328062, 335382, 337872, 343830, 351258, 357780, 425442
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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) = 348 is a term because A014574(348) = 348-(2+2+3+29) = 312 and 348-1 = 347, 348+1 = 349, 312-1 = 311, and 312+1 = 313 are prime.
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MAPLE
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filter:= proc(n) local s, t;
if not isprime(n-1) or not isprime(n+1) then return false fi;
s:= add(t[1]*t[2], t= ifactors(n)[2]);
isprime(n-s-1) and isprime(n-s+1)
end proc:
select(filter, [seq(i, i=6..10^6, 2)]);
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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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