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A331308
a(n) = min(d(n), d(A225546(n))), where d gives the number of divisors of n, A000005.
4
1, 2, 2, 2, 2, 4, 2, 4, 3, 4, 2, 6, 2, 4, 4, 2, 2, 6, 2, 6, 4, 4, 2, 8, 3, 4, 4, 6, 2, 8, 2, 4, 4, 4, 4, 4, 2, 4, 4, 8, 2, 8, 2, 6, 6, 4, 2, 6, 3, 6, 4, 6, 2, 8, 4, 8, 4, 4, 2, 12, 2, 4, 6, 4, 4, 8, 2, 6, 4, 8, 2, 8, 2, 4, 6, 6, 4, 8, 2, 10, 3, 4, 2, 12, 4, 4, 4, 8, 2, 12, 4, 6, 4, 4, 4, 8, 2, 6, 6, 6, 2, 8, 2, 8, 8
OFFSET
1,2
COMMENTS
This is not equal to A000005(A331288(n)). The first difference is at n=100, where a(100) = 6, while A000005(A331288(100)) = 9. Note that A225546(100) = 243 and d(243) = 6 < d(100) = 9.
LINKS
FORMULA
a(n) = min(A000005(n), A331309(n)).
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Jan 21 2020
STATUS
approved