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Primes which remain prime after one and after two applications of the rotate-and-add operation of A086002.
5

%I #15 Aug 22 2015 00:46:29

%S 271,281,10853,10903,10939,12917,12919,16603,16673,16823,16843,18671,

%T 18911,18913,20929,22817,22907,24907,26813,26833,26903,26947,28661,

%U 28901,28921,30809,30829,32831,32917,32941,34939,36653,36913,38651

%N Primes which remain prime after one and after two applications of the rotate-and-add operation of A086002.

%C The rotate operation of nonnegative integers is defined in A086002, which lists the primes that remain prime after one application of the compound rotate-and-add operation. The sequence here lists those primes p which in addition remain prime after applying this transformation twice, that is, those elements of A086002 such that the image of the rotate-and-add operation is again in A086002.

%H Chai Wah Wu, <a href="/A086003/b086003.txt">Table of n, a(n) for n = 1..10000</a>

%F {p in A086002: p+rot(p) in A086002}.

%e a(6)=12917 because (i) 12917 is prime. (ii) rotate(12917) = 17912 and 12917+17912=30829 which is also prime. (iii) rotate(30829) = 29830 and 30829+29830=60659 which is also prime.

%Y Cf. A086002, A086004.

%K base,nonn

%O 1,1

%A Chuck Seggelin (barkeep(AT)plastereddragon.com), Jul 07 2003

%E Edited by _R. J. Mathar_, May 27 2009