A395052 a(n) = A006530(A276085(n)), where A006530 gives the largest prime factor of n, and A276085 is fully additive with a(p) = p#/p.

1, 2, 2, 3, 3, 5, 3, 2, 7, 7, 2, 11, 31, 2, 2, 13, 5, 17, 2, 2, 211, 19, 5, 3, 2311, 3, 2, 23, 3, 29, 5, 53, 509, 3, 3, 31, 277, 17, 3, 37, 11, 41, 53, 5, 27953, 43, 3, 5, 13, 1877, 17, 47, 7, 3, 11, 31907, 703763, 53, 5, 59, 34231, 17, 3, 193, 71, 61, 1877, 22247, 37, 67, 7, 71, 200560490131, 7, 31907, 5, 257, 73

Offset

2,2

Links

Antti Karttunen, Table of n, a(n) for n = 2..465

Formula

a(A000040(n)) = A008578(n).

Prog

(PARI)
A006530(n) = if(n>1, vecmax(factor(n)[, 1]), 1);
A276085(n) = { my(f=factor(n)); sum(k=1, #f~, f[k, 2]*prod(i=1, primepi(f[k, 1]-1), prime(i))); };
A395052(n) = A006530(A276085(n));

Crossrefs

Cf. A000040, A006530, A008578, A276085.

Cf. also A394895, A395042.

Sequence in context: A169897 A254309 A079375 * A069933 A373149 A204987

Adjacent sequences: A395048 A395049 A395051 * A395053 A395054 A395055

Keyword

nonn

Author

Antti Karttunen, Apr 15 2026

Status

approved