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A092128 Numbers n such that n, n+2, n+4, n+6, n+8, n+10 are semiprimes. 10
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; text; internal format)
OFFSET

1,1

COMMENTS

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

LINKS

Table of n, a(n) for n=1..35.

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 &] (* 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 *)

CROSSREFS

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

Sequence in context: A161192 A134670 A250367 * A156410 A156413 A029819

Adjacent sequences:  A092125 A092126 A092127 * A092129 A092130 A092131

KEYWORD

easy,nonn

AUTHOR

Zak Seidov, Feb 22 2004

EXTENSIONS

More terms from Don Reble, Feb 23 2004

More terms from Robert G. Wilson v, Feb 24 2004

STATUS

approved

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Last modified January 16 23:31 EST 2022. Contains 350377 sequences. (Running on oeis4.)