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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A360041 Prime numbers missing from A359137: prime numbers for which none of the nontrivial permutations of its digits (not permitting leading zeros) produces a prime number.

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%I A360041 #9 Jan 23 2023 09:10:00
%S A360041 2,3,5,7,19,23,29,41,43,47,53,59,61,67,83,89,103,109,257,263,269,307,
%T A360041 401,409,431,487,503,509,523,541,601,607,809,827,829,853,859,2017,
%U A360041 2087,2861,4027,4051,4079,4801,5021,5209,5623,5849,6047,6053,6803,8053,8059
%N A360041 Prime numbers missing from A359137: prime numbers for which none of the nontrivial permutations of its digits (not permitting leading zeros) produces a prime number.
%C A360041 Any prime number p >= 10^11 has necessarily a duplicate digit, say that appears at positions i and j. Applying the nontrivial permutation (i j) to the digits of p yields a prime number (p itself), hence p does not belong to the sequence and the sequence is finite.
%e A360041 The nontrivial permutations of the digits of 607 (not permitting leading zeros) are:
%e A360041   670 = 2 * 5 * 67,
%e A360041   706 = 2 * 353,
%e A360041   760 = 2^3 * 5 * 19,
%e A360041 so 607 belongs to the sequence.
%o A360041 (PARI) is(p) = { my (d=digits(p)); if (#d > #Set(d), return (0), forperm (vecsort(d), t, if (t[1], my (q=fromdigits(Vec(t))); if (p!=q && isprime(q), return (0)))); return (1)) }
%Y A360041 Cf. A359136, A359137, A360040.
%K A360041 nonn,base,fini,full
%O A360041 1,1
%A A360041 _Rémy Sigrist_, Jan 23 2023