A376891 Numbers k such that the sum of the first k lesser of twin primes is a lesser of twin prime.

1, 23, 143, 251, 281, 305, 341, 455, 605, 761, 1349, 1613, 2765, 2903, 2981, 3623, 3725, 3923, 4049, 4133, 4745, 5207, 5303, 5489, 5765, 6515, 6611, 7793, 7835, 8153, 8237, 10427, 10697, 11261, 11447, 11627, 11729, 12401, 12701, 13871, 14327, 15359, 15683

Offset: 1

Author

Ilya Gutkovskiy, Oct 08 2024

Keywords

• nonn

Links

• Robert Israel, Table of n, a(n) for n = 1..10000
• Eric Weisstein's World of Mathematics, Twin Primes.

Crossrefs

Cf. A001359, A013916, A071149, A086167, A089228, A376892.

Programs

Maple

K:= 1: count:= 1: s:= 3: k:= 1:
for p from 5 by 6 do
  if isprime(p) and isprime(p+2) then
    k:= k+1;
    s:= s+p;
    if s mod 6 = 5 and isprime(s) and isprime(s+2) then
      count:= count+1; K:= K,k;
      if count = 100 then break fi;
fi fi od:
K; # Robert Israel, Oct 08 2024

Mathematica

Position[Accumulate[Select[Partition[Prime[Range[200000]],2,1],#[[2]]-#[[1]]==2&][[;;,1]]],?(AllTrue[#+{0,2},PrimeQ]&)]//Quiet//Flatten (* _Harvey P. Dale, Jun 24 2025 *)

PARI

lista(nn) = my(v=select(p->isprime(p+2), primes(nn)), s = vector(#v)); s[1] = v[1]; for (i=2, #v, s[i] = s[i-1]+v[i]); Vec(select(x->(isprime(x) && isprime(x+2)), s, 1)); \\ Michel Marcus, Oct 10 2024