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A139075 Primes p arising in A139074. 31
3, 2, 3, 31, 1009, 2, 5702401, 631 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

a(23) = (23+1579!)/23. - Andrew V. Sutherland (drew(AT)math.mit.edu), Apr 11, 2008.

Smallest mother factorial prime p of order n, i.e. smallest prime of the form (p!+n)/n where p is prime.

For smallest daughter factorial prime p of order n see A139074

For smallest father factorial prime p of order n see A139207

For smallest son factorial prime p of order n see A139206

a(9)=26737!/9+1 is a 106758 digit (probable) prime.  Easily calculated but too large to enter here a(10)=13, a(11)=566092801, a(12)=11. [Robert Price, Jan 19 2011]

MATHEMATICA

a = {}; Do[k = 1; While[ ! PrimeQ[(Prime[k]! + n)/n], k++ ]; AppendTo[a, Prime[(Prime[k]! + n)/n]], {n, 1, 8}]; a

CROSSREFS

Cf. A082672, A089085, A089130, A117141, A007749, A139056, A139057, A139058, A139059, A139060, A139061, A139061, A139062, A139063, A139064, A139065, A139066, A020458, A139068, A137390, A139070, A139071, A139072, A139073, A139074, A139074, A139075, A136019, A136020, A136026, A136027.

Sequence in context: A123170 A091806 A139170 * A089750 A109591 A143932

Adjacent sequences:  A139072 A139073 A139074 * A139076 A139077 A139078

KEYWORD

more,nonn

AUTHOR

Artur Jasinski (grafix(AT)csl.pl), Apr 08 2008, Apr 21 2008

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Last modified February 15 20:03 EST 2012. Contains 205852 sequences.