A373846 Numbers k for which A276085(k) is a prime, where A276085 is the primorial base log-function.

3, 4, 6, 8, 10, 14, 18, 22, 24, 26, 32, 50, 54, 70, 72, 74, 90, 96, 98, 120, 128, 154, 160, 182, 242, 250, 270, 286, 338, 350, 360, 374, 378, 442, 450, 480, 486, 490, 494, 504, 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

Offset: 1

Author

Antti Karttunen, Jun 20 2024

Keywords

• nonn

Links

• Antti Karttunen, Table of n, a(n) for n = 1..346

Crossrefs

Positions of primes in A276085.

Positions of 1's in A373842.

Subsequence of A373847.

After two initial terms, a subsequence of A036554.

Programs

PARI

A276085(n) = { my(f = factor(n)); sum(k=1, #f~, f[k, 2]*prod(i=1,primepi(f[k, 1]-1),prime(i))); };
isA373846(n) = isprime(A276085(n));