The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A139061 (Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
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A139061

Numbers n for which (4+n!)/4 is prime.
(history; published version)

#17 by N. J. A. Sloane at Tue Jan 10 23:04:01 EST 2017

STATUS

proposed

approved

#16 by Robert Price at Tue Jan 10 20:56:41 EST 2017

STATUS

editing

proposed

#15 by Robert Price at Tue Jan 10 20:56:12 EST 2017

DATA

4, 5, 6, 13, 21, 25, 32, 40, 61, 97, 147, 324, 325, 348, 369, 1290, 1342, 3167, 6612, 8176, 10990

COMMENTS

a(22) > 25000. - Robert Price, Jan 10 2017

EXTENSIONS

a(19) - a(21) from Robert Price, Jan 10 2017

STATUS

approved

editing

#14 by N. J. A. Sloane at Thu Feb 19 00:07:20 EST 2015

STATUS

proposed

approved

#13 by Serge Batalov at Wed Feb 18 21:12:28 EST 2015

STATUS

editing

proposed

#12 by Serge Batalov at Wed Feb 18 21:12:13 EST 2015

DATA

4, 5, 6, 13, 21, 25, 32, 40, 61, 97, 147, 324, 325, 348, 369, 1290, 1342, 3167

CROSSREFS

Cf. n!/m-1 is a prime: A002982, A082671, A139056, A139199-A139205; n!/m+1 is a prime: A002981, A082672, A089085, A139061, A139058, A139063, A139065, A151913, A137390, A139071 (1<=m<=10).

EXTENSIONS

More terms from Serge Batalov, Feb 18 2015

STATUS

approved

editing

#11 by Charles R Greathouse IV at Thu Nov 21 12:49:20 EST 2013

MATHEMATICA

Select[Range[500], PrimeQ[(4+#!)/4]&] (* From _Harvey P. Dale, _, Mar 24 2011 *)

Discussion

Thu Nov 21

12:49

OEIS Server: https://oeis.org/edit/global/2062

#10 by Charles R Greathouse IV at Mon May 13 01:48:48 EDT 2013

PROG

(PARI) for(n=4, 1e3, if(ispseudoprime(n!/4+1), print1(n", "))) \\ _Charles R Greathouse IV, _, Jul 15 2011

Discussion

Mon May 13

01:48

OEIS Server: https://oeis.org/edit/global/1914

#9 by Russ Cox at Sat Mar 31 10:22:08 EDT 2012

AUTHOR

_Artur Jasinski (grafix(AT)csl.pl), _, Apr 07 2008

Discussion

Sat Mar 31

10:22

OEIS Server: https://oeis.org/edit/global/339

#8 by Charles R Greathouse IV at Fri Jul 15 09:36:06 EDT 2011

STATUS

editing

approved