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A060232
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Smaller of twin primes whose mean (average) is a multiple of A002110(6)=30030.
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3
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180179, 270269, 300299, 330329, 390389, 420419, 540539, 660659, 840839, 1231229, 1261259, 1501499, 1621619, 1861859, 1921919, 1951949, 2012009, 2372369, 2762759, 2972969, 3663659, 3693689, 3723719, 3903899, 4084079
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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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For the pair {5735729,5735731} (5735729+5735731)/2 = 191*30030.
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MAPLE
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for n from 1 to 10^5 do if (ithprime(n+1) - ithprime(n)) = 2 and (ithprime(n+1) + ithprime(n)) mod 30030 = 0 then print(ithprime(n)); fi; od; # Muniru A Asiru, Jan 29 2018
# More efficient:
select(t -> isprime(t) and isprime(t+2), [seq(30030*k-1, k=1..10^3)]); # Robert Israel, Jan 29 2018
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MATHEMATICA
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Select[Partition[Prime[Range[300000]], 2, 1], #[[2]]-#[[1]]==2&&Divisible[Mean[ #], 30030]&][[All, 1]] (* Harvey P. Dale, Apr 23 2022 *)
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PROG
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(GAP) P:=Filtered([1..10^5], IsPrime);;
P1:=List(Filtered(Filtered(List([1..Length(P)-1], n -> [P[n], P[n+1]]), i -> i[2]-i[1]=2), j -> (j[1] + j[2]) mod 30030 = 0), k -> k[1]); # Muniru A Asiru, Jan 29 2018
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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