A104364 - OEIS

%I #9 Apr 09 2024 05:15:22

%S 5,11,59,179,1259,7559,37799,415799,1135133999,5499724229999,

%T 29220034833989999,1408101540804746673385499999,

%U 43673268652925265723884051023987499999

%N Primes of the form A104350(k) - 1.

%H Amiram Eldar, <a href="/A104364/b104364.txt">Table of n, a(n) for n = 1..26</a>

%t Select[FoldList[Times, Array[FactorInteger[#][[-1, 1]] &, 100]] - 1, PrimeQ] (* _Amiram Eldar_, Apr 08 2024 *)

%o (PARI) gpf(n) = {my(p = factor(n)[, 1]); if(n == 1, 1, p[#p]);}

%o lista(nmax) = {my(r = 1); for(k = 1, nmax, r * = gpf(k); if(isprime(r-1), print1(r-1, ", ")));} \\ _Amiram Eldar_, Apr 08 2024

%Y Intersection of A104357 and A000040.

%Y Cf. A104372, A104373, A055490, A057705.

%K nonn

%O 1,1

%A _Reinhard Zumkeller_, Mar 06 2005