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A376891
Numbers k such that the sum of the first k lesser of twin primes is a lesser of twin prime.
2
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
1,2
LINKS
Eric Weisstein's World of Mathematics, Twin Primes.
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
PROG
(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
CROSSREFS
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, Oct 08 2024
STATUS
approved