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A369151
Numbers with a record high excess of even over odd divisors; so indices of record lows in A048272.
2
1, 2, 4, 8, 16, 24, 48, 96, 144, 192, 240, 480, 720, 960, 1440, 2880, 3360, 5040, 6720, 10080, 20160, 30240, 40320, 60480, 80640, 100800, 110880, 181440, 201600, 221760, 332640, 443520, 665280, 887040, 1108800, 1330560, 1995840, 2217600, 2661120, 2882880, 4324320, 5765760, 8648640, 11531520, 14414400
OFFSET
1,2
COMMENTS
Every term is the product of primorials, i.e., this is a subsequence of A025487, i.e., no prime factor of any term has a lower exponent than the following prime has.
LINKS
FORMULA
If n > 2, a(n) = 2*A181808(n-2) = 4*A002182(n-2).
EXAMPLE
24 is a term because 24 has 6 even divisors, {2,4,6,8,12,24}, and 2 odd divisors, {1,3}, giving a difference of 4, more than that of any number less than 24.
CROSSREFS
Cf. A048272.
Sequence in context: A138278 A326078 A089827 * A222089 A182763 A272709
KEYWORD
nonn
AUTHOR
Keith F. Lynch, Jan 14 2024
STATUS
approved