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Numbers k for which A276085(k) is a prime, where A276085 is the primorial base log-function.
4

%I #9 Jun 20 2024 16:26:16

%S 3,4,6,8,10,14,18,22,24,26,32,50,54,70,72,74,90,96,98,120,128,154,160,

%T 182,242,250,270,286,338,350,360,374,378,442,450,480,486,490,494,504,

%U 550,600,630,640,646,648,672,766,800,840,864,896,910,946,986,1078,1120,1152,1274,1334,1350,1394,1458,1536,1610,1666

%N Numbers k for which A276085(k) is a prime, where A276085 is the primorial base log-function.

%H Antti Karttunen, <a href="/A373846/b373846.txt">Table of n, a(n) for n = 1..346</a>

%o (PARI)

%o A276085(n) = { my(f = factor(n)); sum(k=1, #f~, f[k, 2]*prod(i=1,primepi(f[k, 1]-1),prime(i))); };

%o isA373846(n) = isprime(A276085(n));

%Y Positions of primes in A276085.

%Y Positions of 1's in A373842.

%Y Subsequence of A373847.

%Y After two initial terms, a subsequence of A036554.

%K nonn

%O 1,1

%A _Antti Karttunen_, Jun 20 2024