A373349 Twin primes where both the prime and its twin have prime reversals.

3, 5, 7, 11, 13, 71, 73, 149, 151, 179, 181, 311, 313, 1031, 1033, 1151, 1153, 1229, 1231, 3299, 3301, 3371, 3373, 3389, 3391, 3467, 3469, 3851, 3853, 7457, 7459, 7949, 7951, 9011, 9013, 9437, 9439, 10007, 10009, 10067, 10069, 10457, 10459, 10499, 10501, 10889

Offset

1,1

Links

Robert Israel, Table of n, a(n) for n = 1..10001

Maple

R:= n-> (s-> parse(cat(s[-i]$i=1..length(s))))(""||n):
q:= p-> andmap(isprime, [p, R(p)]) and ormap(
    t-> andmap(isprime, [p+t, R(p+t)]), [-2, +2]):
select(q, [$2..12000])[];  # Alois P. Heinz, Jun 06 2024

Prog

(PARI) isrevp(p) = isprime(p) && isprime(fromdigits(Vecrev(digits(p))));
isok(p) = isprime(p) && ((isprime(p+2) && isrevp(p+2)) || (isprime(p-2) &&  isrevp(p-2))) && isrevp(p); \\ Michel Marcus, Jun 06 2024

Crossrefs

Cf. A001097, A007500.

Cf. A004086.

Sequence in context: A288370 A108817 A288892 * A123677 A133954 A087325

Adjacent sequences: A373346 A373347 A373348 * A373350 A373351 A373352

Keyword

nonn,base,changed

Author

Thomas Otten, Jun 01 2024

Status

approved