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A082520 Palindromic Sophie Germain primes: both p and 2p+1 are palindromic primes. 3
2, 3, 5, 191, 19391, 38183, 1508051, 1609061, 1628261, 3717173, 3916193, 161535161, 161838161, 170646071, 172747271, 182949281, 190909091, 352909253, 354848453, 360818063, 364636463, 15052625051, 15150805151, 15253635251 (list; graph; refs; listen; history; text; internal format)
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

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Last modified June 15 15:16 EDT 2021. Contains 345049 sequences. (Running on oeis4.)