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A354609 Carmichael numbers ending in 1.

%I A354609 #32 Jul 26 2022 07:27:14
%S A354609 561,2821,6601,8911,15841,29341,41041,75361,101101,115921,162401,
%T A354609 172081,188461,252601,314821,340561,399001,410041,488881,512461,
%U A354609 530881,552721,656601,658801,838201,852841,1024651,1152271,1193221,1461241,1615681,1857241,1909001,2100901,2113921,2433601,2455921,2704801,3057601
%N A354609 Carmichael numbers ending in 1.
%H A354609 Amiram Eldar, <a href="/A354609/b354609.txt">Table of n, a(n) for n = 1..10000</a>
%H A354609 <a href="/index/Ca#Carmichael">Index entries for sequences related to Carmichael numbers</a>
%t A354609 Select[10*Range[0, 3*10^5] + 1, CompositeQ[#] && Divisible[# - 1, CarmichaelLambda[#]] &] (* _Amiram Eldar_, Jul 08 2022 *)
%o A354609 (Python)
%o A354609 from itertools import islice
%o A354609 from sympy import nextprime, factorint
%o A354609 def A354609_gen(): # generator of terms
%o A354609     p, q = 3, 5
%o A354609     while True:
%o A354609         for n in range(p+2+(-p-1)%10, q, 10):
%o A354609             f = factorint(n)
%o A354609             if max(f.values()) == 1 and not any((n-1) % (p-1) for p in f):
%o A354609                 yield n
%o A354609         p, q = q, nextprime(q)
%o A354609 A354609_list = list(islice(A354609_gen(),30)) # _Chai Wah Wu_, Jul 24 2022
%Y A354609 Intersection of A002997 and A017281.
%Y A354609 Cf. A352970, A355305, A355307, A355309.
%K A354609 nonn,base
%O A354609 1,1
%A A354609 _Omar E. Pol_, Jul 08 2022