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A076186 Numbers n such n!! + 2^2 is prime. 9
1, 3, 5, 7, 11, 17, 29, 39, 43, 73, 93, 315, 549, 2059, 5543, 6937, 22819 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

a(18) > 30,000 - Robert Price, Oct 04 2012

LINKS

Table of n, a(n) for n=1..17.

The OpenPFGW Project, Primality Tester

Henri & Renaud Lifchitz, PRP Records.

Joe McLean, Interesting Sources of Probable Primes

CROSSREFS

Cf. A006882, A080778 and A076185, A076188, A076189, A076190, A076193, A076194, A076195, A076196, A076197 for other values of s in n!! + 2^s.

Sequence in context: A109543 A229168 A091567 * A092564 A068811 A088083

Adjacent sequences:  A076183 A076184 A076185 * A076187 A076188 A076189

KEYWORD

nonn,more

AUTHOR

Zak Seidov, Nov 02 2002

EXTENSIONS

Edited and extended (n<4096) by Hugo Pfoertner, Jun 19 2003

6937 from Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 03 2008

Corrected by Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 03 2008

a(17) = 22819 from Robert Price, Oct 04 2012

STATUS

approved

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Last modified April 20 13:42 EDT 2014. Contains 240806 sequences.