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A086361 a(n)=A085956(3n). 12
13, 61, 127, 73, 61, 397, 211, 97, 163, 181, 463, 5689, 547, 1093, 271, 673, 1123, 10909, 229, 241, 4663, 661, 967, 1873, 7951, 1093, 16363, 5209, 349, 541, 373, 7873, 397, 409, 421, 433, 4219, 9349, 15679, 1201, 1723, 7309, 15739, 3433, 811, 1933 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..46.

EXAMPLE

n=144:3n=432,6n=864, a(144)=120097 prime with (120097-1)/864=139 prime and with 864.12097+1=103763809 prime.

PROG

(PARI) a(n) = {n = 3*n; p = 2; while (!(isprime(2*n*p+1) && (type(q=(p-1)/(2*n))== "t_INT") && isprime(q)), p = nextprime(p+1)); p; } \\ Michel Marcus, Feb 25 2014

CROSSREFS

Cf. A085956, A086362.

Sequence in context: A087106 A142402 A140615 * A119151 A081589 A270449

Adjacent sequences:  A086358 A086359 A086360 * A086362 A086363 A086364

KEYWORD

nonn

AUTHOR

Labos Elemer, Jul 22 2003

STATUS

approved

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Last modified May 6 05:18 EDT 2021. Contains 343580 sequences. (Running on oeis4.)