A332968 Lesser of twin primes p, p+2 such that prime(p) and prime(p+2) are also twin primes.

3, 5, 11, 41, 461, 1031, 1619, 2309, 2789, 7877, 8219, 9929, 11117, 12071, 16067, 18251, 18911, 22091, 23909, 26681, 28751, 30467, 32531, 33809, 38747, 40847, 41201, 41609, 43397, 46769, 49169, 56711, 58907, 73061, 79631, 89069, 91457, 92957, 96179, 110567, 113327, 114641, 117989, 122399, 123491

Offset

1,1

Links

Chai Wah Wu, Table of n, a(n) for n = 1..10000 (n = 1..699 from Robert Israel)

Example

a(3) = 11 is a member because it is the lesser of the twin prime pair (11,13), and prime(11) = 31 and prime(13) = 41 are both twin primes.

Maple

P:= select(isprime, [2, seq(i, i=3..2*10^5, 2)]):
nP:= nops(P):
T:= P[select(i-> P[i+1]=P[i]+2, [$1..nP-1])]:
TS:= select(`<=`, T, nP-3):
select(t -> (P[t]+2=P[t+1] or P[t]-2=P[t-1]) and (P[t+2]+2=P[t+3] or P[t+2]-2=P[t+1]), TS);

Crossrefs

Cf. A001359, A006450.

Sequence in context: A055511 A236457 A105236 * A144467 A387192 A049883

Adjacent sequences: A332965 A332966 A332967 * A332969 A332970 A332971

Keyword

nonn

Author

J. M. Bergot and Robert Israel, Mar 04 2020

Status

approved