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A092128
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Numbers n such that n, n+2, n+4, n+6, n+8, n+10 are semiprimes.
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10
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1383, 3091, 3093, 5609, 8129, 8131, 8133, 9753, 9983, 9985, 9987, 10401, 11013, 12053, 13637, 16499, 22457, 30991, 43339, 45803, 49083, 53761, 55559, 55561, 58277, 63047, 63951, 64829, 69603, 71727, 76803, 80633, 92603, 92605, 98493
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OFFSET
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1,1
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COMMENTS
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Semiprimes in arithmetic progression. All terms are odd, see also A056809.
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LINKS
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MATHEMATICA
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PrimeFactorExponentsAdded[n_] := Plus @@ Flatten[Table[ #[[2]], {1}] & /@ FactorInteger[n]]; Select[ Range[ 99210], PrimeFactorExponentsAdded[ # ] == PrimeFactorExponentsAdded[ # + 2] == PrimeFactorExponentsAdded[ # + 4] == PrimeFactorExponentsAdded[ # + 6] == PrimeFactorExponentsAdded[ # + 8] == PrimeFactorExponentsAdded[ # + 10] == 2 &] (* Robert G. Wilson v, Feb 24 2004 *)
spQ[n_]:=PrimeOmega[n]==2; Select[Range[100000], AllTrue[#+{0, 2, 4, 6, 8, 10}, spQ]&] (* Harvey P. Dale, Dec 19 2021 *)
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CROSSREFS
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KEYWORD
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easy,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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