A082520 Palindromic Sophie Germain primes: both p and 2p+1 are palindromic primes.

2, 3, 5, 191, 19391, 38183, 1508051, 1609061, 1628261, 3717173, 3916193, 161535161, 161838161, 170646071, 172747271, 182949281, 190909091, 352909253, 354848453, 360818063, 364636463, 15052625051, 15150805151, 15253635251

Offset

1,1

Comments

Subsequence of A051835 (intersection of A002385 and A005384).

References

H. Dubner, "Palindromic Sophie Germain primes", Journal of Recreational Mathematics, Vol. 26(1):38-41 1994 Baywood Inc. NY

Links

Dmitry Petukhov, Table of n, a(n) for n = 1..804 (terms up to 10^15).

H. Dubner, Palindromic Sophie Germain Primes

Example

3916193 is in the sequence because both 3916193 and 2*3916193 + 1 = 7832387 are palindromic primes.

Mathematica

Select[Prime@Range@1000000, PalindromeQ@#&&PalindromeQ[2#+1]&&PrimeQ[2#+1]&] (* Giorgos Kalogeropoulos, May 14 2021 *)

Crossrefs

Cf. A002385, A005384, A051835.

The associated primes are listed in A082565.

Sequence in context: A140551 A064936 A041655 * A062597 A038526 A082755

Adjacent sequences: A082517 A082518 A082519 * A082521 A082522 A082523

Keyword

base,nonn

Author

Lekraj Beedassy, Apr 30 2003

Status

approved