A357252 Primes in A357251.

19, 14479, 43609, 406171, 711959, 1330177, 2698231, 3918157, 18987169, 26135339, 194727347, 269998639, 975929347, 5005853669, 8430389621, 24830247671, 36372313009, 69703708967, 93194681917, 126628534313, 139478926201, 304123612349, 359101509211, 384305009171, 387550106843, 400722388999

Offset

1,1

Comments

Primes that are, for some N, the sum of p*q for all pairs of primes (p,q) with p <= q <= N.

Links

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

Example

a(2) = 14479 is in the sequence because 14479 = A357251(11) is the sum of p*q for primes p <= q <= 31 and is prime.

Maple

p:= 2: a:= 4: s:= 2: R:= NULL: count:= 0:
for i from 1 while count < 100 do
  p:= nextprime(p);
  s:= s + p;
  a:= a + p*s;
  if isprime(a) then count:= count+1; R:= R, a; fi
od:
R;

Crossrefs

Cf. A357251.

Sequence in context: A265169 A174306 A270069 * A186165 A198412 A110392

Adjacent sequences: A357249 A357250 A357251 * A357253 A357254 A357255

Keyword

nonn

Author

J. M. Bergot and Robert Israel, Sep 20 2022

Status

approved