OFFSET
0,1
LINKS
Robert Israel, Table of n, a(n) for n = 0..1000
EXAMPLE
a(3) = 13 because there are 3 primes q < 13 with 2*13+q prime, namely 2*13+3 = 29, 2*13+5 = 31, 2*13+11 = 37, and no prime < 13 has exactly 3 such primes.
MAPLE
P:= [seq(ithprime(i), i=1..10000)]:
M:= 100: V:= Array(0..M): count:= 0:
for k from 1 to 10000 while count < M+1 do
v:= nops(select(isprime, {seq(2*P[k]+P[j], j=1..k-1)}));
if v <= M and V[v] = 0 then
count:= count+1; V[v]:= P[k];
fi
od:
convert(V, list);
MATHEMATICA
cnt[p_] := Count[Range[2, p - 1], _?(PrimeQ[#] && PrimeQ[2*p + #] &)]; seq[m_] := Module[{s = Table[0, {m}], c = 0, p = 1, i}, While[c < m, p = NextPrime[p]; i = cnt[p] + 1; If[i <= m && s[[i]] == 0, c++; s[[i]] = p]]; s]; seq[50] (* Amiram Eldar, Dec 13 2021 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
J. M. Bergot and Robert Israel, Dec 13 2021
STATUS
approved