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Numbers p such that p, 2p-1, 3p-2, 4p-3, 5p-4, 6p-5, 7p-6, 8p-7 are primes.
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%I #12 Mar 01 2023 13:38:40

%S 512821,22240681,26486461,99597961,593009341,1021157551,1041298441,

%T 1281196561,1349985001,1426148011,1660907431,1894757971,2544774541,

%U 3590232241,3958824871,4012463281,4219580191,4363137241,6482599411,7178651971,8051820421,8417194381

%N Numbers p such that p, 2p-1, 3p-2, 4p-3, 5p-4, 6p-5, 7p-6, 8p-7 are primes.

%C Each term is 1 modulo 210.

%C The subset p, 2p-1, 4p-3, 8p-7 is a Cunningham chain of the 2nd kind, cf. A057327.

%H Jeppe Stig Nielsen, <a href="/A336060/b336060.txt">Table of n, a(n) for n = 1..50</a>

%H Wikipedia, <a href="http://en.wikipedia.org/wiki/Cunningham_chain">Cunningham chain</a>

%t Select[Prime[Range[387*10^6]],AllTrue[Table[n #-(n-1),{n,2,8}],PrimeQ]&] (* _Harvey P. Dale_, Mar 01 2023 *)

%Y Cf. A005382, A057327, A101769, A336059.

%K nonn

%O 1,1

%A _Jeppe Stig Nielsen_, Jul 07 2020