A393322 - OEIS

%I #20 Feb 21 2026 13:34:22

%S 2,3,5,7,11,37,73,143787341,11853735811

%N Prime numbers prime(i) such that reversal(prime(i)) = prime(reversal(i)).

%C Prime numbers prime(i) with the mirror property (see the Pomerance, Spicer article in Links, section 1. and 6.).

%H Carl Pomerance and Chris Spicer, <a href="https://doi.org/10.1080/00029890.2019.1626672">Proof of the Sheldon Conjecture</a>, The American Mathematical Monthly, September 2019, 126(8), 688-698.

%F a(n) = prime(A069469(n)) = A000040(A069469(n)).

%e For prime(12) = 37: reversal(37) = prime(reversal(12)) which is true because 73 = prime(21), thus 37 is a term.

%t q[k_]:=IntegerReverse[Prime[k]]==Prime[IntegerReverse[k]];Prime[Select[Range[10^5],q]] (* _James C. McMahon_, Feb 16 2026 *)

%Y Cf. A000040, A000720, A046941, A069469.

%K nonn,base,more

%O 1,1

%A _Ctibor O. Zizka_, Feb 11 2026