A344699 a(n) = A344697(A108951(n)).

1, 1, 1, 6, 1, 6, 1, 4, 72, 6, 1, 4, 1, 6, 72, 24, 1, 48, 1, 4, 72, 6, 1, 24, 2160, 6, 18, 4, 1, 48, 1, 16, 72, 6, 2160, 288, 1, 6, 72, 24, 1, 48, 1, 4, 18, 6, 1, 16, 5760, 288, 72, 4, 1, 108, 2160, 24, 72, 6, 1, 288, 1, 6, 18, 96, 2160, 48, 1, 4, 72, 288, 1, 64, 1, 6, 108, 4, 5760, 48, 1, 16, 2592, 6, 1, 288, 2160

Offset

1,4

Links

Antti Karttunen, Table of n, a(n) for n = 1..10201

Index entries for sequences related to primorial numbers

Index entries for sequences related to sigma(n)

Prog

(PARI)
A034386(n) = prod(i=1, primepi(n), prime(i));
A108951(n) = { my(f=factor(n)); prod(i=1, #f~, A034386(f[i, 1])^f[i, 2]) };
A001615(n) = if(1==n, n, my(f=factor(n)); prod(i=1, #f~, f[i, 1]^f[i, 2] + f[i, 1]^(f[i, 2]-1))); \\ After code in A001615
A344697(n) = { my(u=A001615(n)); (u/gcd(u, sigma(n))); };
A344699(n) = A344697(A108951(n));

Crossrefs

Cf. A000203, A001615, A108951, A337203, A344697, A344698, A344701 (apparently positions of records).

Sequence in context: A138116 A348999 A349000 * A010687 A176355 A109918

Adjacent sequences: A344696 A344697 A344698 * A344700 A344701 A344702

Keyword

nonn

Author

Antti Karttunen, May 26 2021

Status

approved