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A132170 Primes of the form (3pq - q - 6)/(3p + 1), where p and q are prime. 0
5, 7, 11, 13, 17, 29, 37, 47, 53, 97, 101, 107, 109, 127, 137, 149, 151, 157, 179, 181, 197, 257, 263, 269, 277, 293, 307, 313, 317, 337, 347, 349, 373, 389, 397, 457, 461, 487, 509, 541, 547, 557, 569, 571, 577, 587, 599, 607, 613, 641, 643, 647, 661, 673 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

5/7 q - 1 < a(n) < q and p <= (2q + 5)/3, so membership can be tested in finite time.

LINKS

Table of n, a(n) for n=1..54.

EXAMPLE

a(1) = (3*3*7 - 7 - 6)/(3*3 + 1) = 5.

a(2) = (3*2*11 - 11 - 6)/(3*2 + 1) = 7.

PROG

(PARI) /* Lists the members with q <= lim */ list(lim)=my(v=[], t); forprime(q=2, lim, forprime(p=2, (2*q+5)\3, t=q-(2*q+6)/(3*p+1); if(denominator(t)==1&&isprime(t), v=concat(v, t)))); vecsort(v, , 8)

CROSSREFS

Sequence in context: A102386 A038958 A109416 * A106309 A227576 A114262

Adjacent sequences:  A132167 A132168 A132169 * A132171 A132172 A132173

KEYWORD

nonn

AUTHOR

Juri-Stepan Gerasimov, Aug 28 2008

EXTENSIONS

Corrected and rewritten by Charles R Greathouse IV, Mar 25 2010

STATUS

approved

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Last modified July 8 07:34 EDT 2020. Contains 335513 sequences. (Running on oeis4.)