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A126711
Primes of the form pqrs+2 with p,q,r,s odd primes.
1
83, 137, 191, 227, 317, 353, 443, 461, 587, 821, 827, 839, 857, 877, 977, 1031, 1091, 1109, 1163, 1277, 1289, 1307, 1367, 1427, 1433, 1451, 1523, 1619, 1627, 1667, 1787, 1811, 1847, 1913, 1973, 1997, 2243, 2333, 2377, 2417, 2543, 2621, 2657, 2693
OFFSET
1,1
LINKS
Charles R Greathouse IV, Table of n, a(n) for n = 1..10000
FORMULA
{A014613(i)+2 such that A014613(i)+2 is in A000040}.
EXAMPLE
a(1) = 83 = 3*3*3*3+2.
a(2) = 137 = 3*3*3*5+2.
a(3) = 191 = 3*3*3*7+2.
a(4) = 227 = 3*3*5*5+2.
MATHEMATICA
With[{nn=50}, Take[Select[Union[Times@@@Tuples[Prime[Range[2, nn]], 4]+2], PrimeQ], nn]] (* Harvey P. Dale, Oct 18 2013 *)
PROG
(Sage) is_A126711 = lambda n: is_prime(n) and sum(m for p, m in factor(n-2)) == 4 # [D. S. McNeil, Dec 11 2010]
(PARI) list(lim)=my(t, tt, v=List()); forprime(p=3, lim\27, forprime(q=p, lim\p\9, forprime(r=q, lim\p\q\3, t=p*q*r; forprime(s=r, lim\t, if(ispseudoprime(tt=t*s+2), listput(v, tt)))))); vecsort(Vec(v)) \\ Charles R Greathouse IV, Feb 17 2011
KEYWORD
easy,nonn
AUTHOR
Jonathan Vos Post, Feb 12 2007
EXTENSIONS
Corrected (299 removed) by D. S. McNeil, Dec 10 2010
STATUS
approved