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A152867 Beginnings of maximal chains of primes with four members (three links). 8
13, 89, 809, 4561, 6689, 7603, 11321, 16493, 18229, 22153, 24107, 28409, 28687, 29153, 32749, 33013, 54493, 55663, 63337, 63419, 67169, 86011, 90289, 108881, 113647, 116929, 132589, 133187, 136033, 136403, 137791, 145543, 147353, 150583 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

For definitions see A152658, of which this is a subsequence.

LINKS

Klaus Brockhaus, Table of n, a(n) for n=1..1000

EXAMPLE

First maximal chain of primes with four members (three links) is 13, 17, 19, 23; the linking primes are 197, 271, 359.

PROG

(PARI) {n=1; while(n<13900, c=0; a=prime(n); while(isprime(n*prime(n)+(n+1)*prime(n+1)), c++; n++); if(c==3, print1(a, ", ")); n++)}

CROSSREFS

Cf. A152658 (beginnings of maximal chains of primes), A152735 (count of links in n-th maximal chain of primes), A152962 (beginning of the first maximal chain of primes with n links), A152865, A152866, A152868, A152869, A152963, A152964.

Sequence in context: A082099 A282858 A268746 * A026912 A161465 A162300

Adjacent sequences:  A152864 A152865 A152866 * A152868 A152869 A152870

KEYWORD

nonn

AUTHOR

Klaus Brockhaus, Dec 17 2008

STATUS

approved

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Last modified April 9 19:36 EDT 2020. Contains 333362 sequences. (Running on oeis4.)