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A297408 Where the prime race among 10k+1, ..., 10k+9 changes leader.

%I A297408 #21 Dec 20 2022 22:51:05
%S A297408 2,13,157,193,347,383,587,673,907,1163,1327,1483,1907,1933,2897,4723,
%T A297408 5557,5573,6037,6113,6637,6673,7487,8273,8317,8363,8387,8443,8467,
%U A297408 8573,8647,8803,8837,8933,9277,9293,10067,10103,11897,11923,12037,12073,12107,12143
%N A297408 Where the prime race among 10k+1, ..., 10k+9 changes leader.
%C A297408 A007355 appears to be an erroneous version of this sequence.
%H A297408 Michael S. Branicky, <a href="/A297408/b297408.txt">Table of n, a(n) for n = 1..10000</a>
%H A297408 Robert G. Wilson v, <a href="/A005596/a005596.pdf">Letter to N. J. A. Sloane, Aug. 1993</a>
%o A297408 (PARI) a297408(limit)={my(v=vector(10),vm=0,ivm=0,imv); forprime(p=2,limit,my(m=p%10);v[m]++;my(mv=vecmax(v,&imv));if(mv>vm,if(imv!=ivm,print1(p,", "); ivm=imv);vm=mv))};
%o A297408 a297408(12500) \\ _Hugo Pfoertner_, Jul 25 2021
%o A297408 (Python)
%o A297408 from sympy import nextprime
%o A297408 from itertools import islice
%o A297408 def agen():
%o A297408     c, p, leader = [0 for i in range(10)], 1, None
%o A297408     while True:
%o A297408         p = nextprime(p); last = p%10; c[last] += 1; m = max(c)
%o A297408         if c.count(m) == 1 and c.index(m) == last and last != leader:
%o A297408             yield p; leader = last
%o A297408 print(list(islice(agen(), 44))) # _Michael S. Branicky_, Dec 20 2022
%Y A297408 Cf. A007352, A007350, A007353, A007354, A274121, A274122, A274123, A297406, A297407, A297408, A297410, A297411.
%K A297408 nonn
%O A297408 1,1
%A A297408 _Sean A. Irvine_, Dec 29 2017