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A339953 Primes of the form (p + 2*q + r)/6 where p, q and r are consecutive primes. 2
5, 7, 11, 13, 29, 47, 67, 71, 73, 83, 131, 151, 233, 307, 461, 467, 479, 571, 577, 587, 613, 619, 643, 727, 853, 947, 953, 967, 991, 1063, 1093, 1231, 1249, 1291, 1297, 1427, 1489, 1493, 1867, 1871, 1879, 2017, 2083, 2111, 2251, 2309, 2311, 2473, 2749, 2753, 2767, 3011, 3089, 3191, 3313, 3691 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Robert Israel, Table of n, a(n) for n = 1..10000

FORMULA

a(n) = (A151799(A339954(n))+2*A339954(n)+A151800(A339954(n)))/6.

EXAMPLE

a(3) = 11 is a term because 13, 17, 19 are consecutive primes with (13+2*17+19)/6 = 11 and 11 is prime.

MAPLE

q:= 2: r:= 3:

count:= 0: R:= NULL:

while count < 100 do

   p:= q; q:= r; r:= nextprime(r);

   w:= (p+2*q+r)/6;

   if w::integer and isprime(w) then

    count:= count+1; R:= R, w;

   fi

od:

R;

CROSSREFS

Cf. A151799, A151800, A339954.

Sequence in context: A265006 A135930 A163429 * A220951 A136055 A250127

Adjacent sequences:  A339950 A339951 A339952 * A339954 A339955 A339956

KEYWORD

nonn

AUTHOR

J. M. Bergot and Robert Israel, Dec 24 2020

STATUS

approved

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Last modified December 4 11:27 EST 2021. Contains 349486 sequences. (Running on oeis4.)