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A243457 Primes p such that (p reversed)-2 is also a prime. 6

%I #15 Sep 08 2022 08:46:08

%S 5,7,13,19,31,37,127,139,151,163,181,193,307,313,331,349,367,379,547,

%T 571,577,991,997,1009,1033,1051,1117,1123,1129,1171,1201,1213,1231,

%U 1249,1279,1297,1321,1327,1399,1429,1453,1459,1489,1543,1567,1579,1597,1609

%N Primes p such that (p reversed)-2 is also a prime.

%H Vincenzo Librandi, <a href="/A243457/b243457.txt">Table of n, a(n) for n = 1..1000</a>

%t Select[Prime[Range[2, 5000]], PrimeQ[FromDigits[Reverse[IntegerDigits[#]]] - 2] &]

%o (Magma) [p: p in PrimesInInterval(2, 2000) | IsPrime(q-2) where q is Seqint(Reverse(Intseq(p)))];

%Y Cf. Primes p such that (p reversed)-k is also a prime: A167216 (k=1), this sequence (k=2), A243458 (k=3), A167513 (k=4), A243459 (k=5), A167488 (k=6), A243460 (k=7), A167497 (k=8), A243461 (k=9), A167496 (k=10).

%K nonn,base

%O 1,1

%A _Vincenzo Librandi_, Jun 05 2014

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Last modified April 17 22:23 EDT 2024. Contains 371767 sequences. (Running on oeis4.)