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%I #13 Dec 30 2020 04:11:02
%S 2,3,5,7,11,23,29,31,47,59,71,127,167,179,191,223,239,359,383,389,419,
%T 431,479,719,839,863,971,1151,1259,1279,1439,1511,2111,2309,2591,2687,
%U 2699,2879,3023,3119,3359,3583,3779,5039,5119,5399,6047,6143,6299,6719
%N Smallest prime p such that the prime signature of p+1 has not occurred earlier.
%H Amiram Eldar, <a href="/A087521/b087521.txt">Table of n, a(n) for n = 1..1200</a>
%H <a href="/index/Pri#prime_signature">Index entries for sequences related to prime signature</a>
%t sig[n_] := Sort @ FactorInteger[n][[;; , 2]]; seq = {}; sigs = {}; Do[If[PrimeQ[p] && !MemberQ[sigs, (s = sig[p + 1])], AppendTo[seq, p]; AppendTo[sigs, s]], {p, 2, 7000}]; seq (* _Amiram Eldar_, Dec 30 2020 *)
%Y Cf. A087520.
%K nonn
%O 1,1
%A _Amarnath Murthy_, Sep 11 2003
%E Edited by _Ray Chandler_, Sep 14 2003
%E Offset corrected by _Amiram Eldar_, Dec 30 2020
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