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A166009 Primes of the form 7+2*(some other prime). 1
11, 13, 17, 29, 41, 53, 89, 101, 113, 149, 173, 233, 269, 281, 353, 389, 401, 461, 509, 521, 569, 593, 641, 701, 773, 809, 929, 941, 1013, 1049, 1181, 1193, 1289, 1301, 1361, 1373, 1409, 1493, 1553, 1601, 1721, 1733, 1889, 1901, 1913, 1949, 1973, 2069, 2129 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

Starting with n=3 both A166009(n) and A023206(n) == 5 mod 6. [From Zak Seidov (zakseidov(AT)yahoo.com), Oct 23 2009]

FORMULA

a(n) = 7+2*A023206(n). - R. J. Mathar, Oct 05 2009

EXAMPLE

p=2 contributes 11=7+2*2. p=3 contributes 13=7+2*3. p=5 contributes 17=7+2*5.

MATHEMATICA

Clear[lst, n, f] f[n_]:=PrimeQ[(n-1)/2-3]; lst={}; Do[p=Prime[n]; If[f[p], AppendTo[lst, p]], {n, 7!}]; lst [From Vladimir Orlovsky (4vladimir(AT)gmail.com), Oct 13 2009]

s={11, 13}; Do[If[PrimeQ[n]&&PrimeQ[(n-7)/2], AppendTo[s, n]], {n, 17, 10^3, 6}]; s [From Zak Seidov (zakseidov(AT)yahoo.com), Oct 23 2009]

Select[2#+7&/@Prime[Range[200]], PrimeQ] [From Harvey P. Dale, Dec. 15, 2010]

CROSSREFS

Cf. A023206. [From Zak Seidov (zakseidov(AT)yahoo.com), Oct 23 2009]

Sequence in context: A006489 A032621 A052031 * A105892 A111337 A162237

Adjacent sequences:  A166006 A166007 A166008 * A166010 A166011 A166012

KEYWORD

nonn

AUTHOR

Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Oct 04 2009

EXTENSIONS

1089 replaced by 1049 - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Oct 05 2009

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Last modified February 15 23:53 EST 2012. Contains 205860 sequences.