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A129655
Numbers that set a new record for number of Fibonacci divisors.
4
1, 2, 6, 24, 120, 720, 5040, 55440, 720720, 12252240, 232792560, 6750984240, 276790353840, 12732356276640, 523410559111440, 24076885719126240, 1131613628798933280, 100713612963105061920, 20042008979657907322080
OFFSET
1,2
COMMENTS
From Donovan Johnson, Jul 07 2009: (Start)
a(15) <= 598420745002080,
a(16) <= 36503665445126880,
a(17) <= 1131613628798933280,
a(18) <= 100713612963105061920. (End)
From Robert Israel, Sep 26 2019: (Start)
a(15) <= 523410559111440,
a(16) <= 24076885719126240. (End)
From David A. Corneth, Sep 27 2019: (Start)
a(19) <= 20042008979657907322080,
a(20) <= 4669788092260292406044640,
a(21) <= 1312210453925142166098543840,
a(22) <= 414821946023574034721351415840,
a(23) <= 116564966832624303756699747851040,
a(24) <= 37417354353272401505900619060183840,
a(25) <= 19494441618054921184574222530355780640,
a(26) <= 31132623264033709131765033380978181682080,
a(27) <= 67277598873576845433744237136293850614974880. (End)
From a(1) up to a(14), last known term, this sequence is equivalent to: a(n) is the smallest number that has exactly n Fibonacci divisors (A000045). The products of the new Fibonacci divisors that appear successively are in A349100. - Bernard Schott, Jul 15 2022
REFERENCES
J. Earls, Red Zen, Lulu Press, NY, 2006, p. 105.
FORMULA
a(n) <= A035105(n+1). - Daniel Suteu, Sep 27 2019
EXAMPLE
5040 has 60 divisors with 7 of them being Fibonacci numbers, namely 1, 2, 3, 5, 8, 21 and 144.
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Jason Earls, May 19 2007
EXTENSIONS
More terms from Donovan Johnson, Feb 26 2008
a(14) from Donovan Johnson, Jul 07 2009
a(15)-a(19) confirmed by David A. Corneth, Sep 06 2024
STATUS
approved