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A117708 Numbers that are both lucky numbers and Chen primes. 0
3, 7, 13, 31, 37, 67, 127, 211, 307, 409, 487, 541, 577, 631, 769, 787, 937, 991, 1009, 1039, 1117, 1201, 1291, 1459, 1471, 1567, 1777, 1801, 2251, 2281, 2467, 2557, 2647, 2971, 3037, 3187, 3259, 3307, 3559, 3709, 3847, 3889, 4441, 4567, 4801, 4969, 4987 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

MATHEMATICA

lst = Range[1, 5000, 2]; i = 2; While[ i <= (len = Length@lst) && (k = lst[[i]]) <= len, lst = Drop[lst, {k, len, k}]; i++ ]; chenQ[n_] := PrimeQ[n] && Plus @@ Last /@ FactorInteger[n + 2] < 3; Select[lst, chenQ@# &] - Robert G. Wilson v (rgwv(at)rgwv.com), May 12 2006

CROSSREFS

Cf. A031157, A109611.

Cf. A031157, A109611.

Sequence in context: A136051 A100750 A105435 * A093431 A083520 A162869

Adjacent sequences:  A117705 A117706 A117707 * A117709 A117710 A117711

KEYWORD

nonn

AUTHOR

Jani Melik (jani_melik(AT)hotmail.com), Apr 27 2006

EXTENSIONS

Corrected and extended by Robert G. Wilson v (rgwv(at)rgwv.com), May 12 2006

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Last modified February 17 00:09 EST 2012. Contains 205978 sequences.