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%I #13 Oct 25 2024 16:30:28
%S 2,5,13,17,37,41,61,73,89,97,101,109,113,157,181,193,233,241,257,277,
%T 281,313,337,349,353,397,401,409,421,433,449,457,461,521,541,577,593,
%U 601,613,617,641,661,673,701,733,757,761,769,821,829,877,881,929,937
%N Primes p such that p-1 can be written as a product of smaller numbers that are also of the form prime-1.
%C Except for 2, this is a subsequence of primes of the form 4k+1 (A002144). - _Davide Rotondo_, Oct 07 2024
%e 2 is a term because 2 is prime and 2-1 = 1 equals the empty product.
%e 5 is a term because 5 is prime, 5-1 = 2*2 = (3-1)*(3-1), and 3 is prime.
%e 3329 is a term because 3329 is prime, 3329-1 = 4*16*52 = (5-1)*(17-1)*(53-1), and 5, 17, and 53 are prime. (This is the first term that requires more than two factors.)
%Y Cf. A006093, A363636, A363638.
%Y Cf. A002144.
%K nonn
%O 1,1
%A _Pontus von Brömssen_, Jun 19 2023