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A092127 Numbers n such that n, n+2, n+4, n+6, n+8 are semiprimes. 9
213, 1133, 1343, 1383, 1385, 1835, 1937, 2315, 2807, 3091, 3093, 3095, 3147, 3977, 4313, 4529, 4835, 5089, 5609, 5611, 6185, 6533, 7141, 8129, 8131, 8133, 8135, 9753, 9755, 9983, 9985, 9987, 9989, 10401, 10403, 11013, 11015, 11099, 11663, 12053 (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..40.

MATHEMATICA

PrimeFactorExponentsAdded[n_] := Plus @@ Flatten[Table[ #[[2]], {1}] & /@ FactorInteger[n]]; Select[ Range[ 12054], PrimeFactorExponentsAdded[ # ] == PrimeFactorExponentsAdded[ # + 2] == PrimeFactorExponentsAdded[ # + 4] == PrimeFactorExponentsAdded[ # + 6] == PrimeFactorExponentsAdded[ # + 8] == 2 &] (* Robert G. Wilson v, Feb 24 2004 *)

CROSSREFS

Cf. A056809, A070552, A092125, A092126, A092128, A092129.

Sequence in context: A251146 A085309 A252024 * A082967 A212312 A201342

Adjacent sequences:  A092124 A092125 A092126 * A092128 A092129 A092130

KEYWORD

easy,nonn

AUTHOR

Zak Seidov, Feb 22 2004

STATUS

approved

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Last modified May 23 16:52 EDT 2017. Contains 286925 sequences.