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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 (list; graph; refs; listen; history; text; internal format)
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

CROSSREFS

Cf. A000040, A014613, A126608-A126609, A126636, A126660-A126661.

Sequence in context: A140038 A260495 A165502 * A039548 A141976 A142652

Adjacent sequences:  A126708 A126709 A126710 * A126712 A126713 A126714

KEYWORD

easy,nonn

AUTHOR

Jonathan Vos Post, Feb 12 2007

EXTENSIONS

Corrected (299 removed) by D. S. McNeil, Dec 10 2010

STATUS

approved

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Last modified June 13 04:23 EDT 2021. Contains 344980 sequences. (Running on oeis4.)