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A092128 Numbers n such that n, n+2, n+4, n+6, n+8, n+10 are semiprimes. 9
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 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

Semiprimes in arithmetic progression. All terms are odd, see also A056809.

MATHEMATICA

PrimeFactorExponentsAdded[n_] := Plus @@ Flatten[Table[ #[[2]], {1}] & /@ FactorInteger[n]]; Select[ Range[ 99210], PrimeFactorExponentsAdded[ # ] == PrimeFactorExponentsAdded[ # + 2] == PrimeFactorExponentsAdded[ # + 4] == PrimeFactorExponentsAdded[ # + 6] == PrimeFactorExponentsAdded[ # + 8] == PrimeFactorExponentsAdded[ # + 10] == 2 &] (from Robert G. Wilson v Feb 24 2004)

CROSSREFS

Cf. A056809, A070552, A092125, A092126, A092127, A092129.

Sequence in context: A134671 A161192 A134670 * A156410 A156413 A029819

Adjacent sequences:  A092125 A092126 A092127 * A092129 A092130 A092131

KEYWORD

easy,nonn

AUTHOR

Zak Seidov (zakseidov(AT)yahoo.com), Feb 22 2004

EXTENSIONS

More terms from Don Reble (djr(AT)nk.ca), Feb 23 2004

More terms from Robert G. Wilson v (rgwv(AT)rgwv.com), Feb 24 2004

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Last modified February 14 08:34 EST 2012. Contains 205614 sequences.