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A375196
Smaller of two successive terms of A025487 that have an equal number of divisors.
2
6, 24, 72, 210, 5400, 30720, 36960, 51840, 53760, 120120, 264600, 887040, 3991680, 6912000, 14968800, 22118400, 58198140, 319334400, 1703116800, 4151347200, 6273146880, 12247200000, 31757806080, 42343741440, 47636709120, 70572902400, 238378140000, 442810368000
OFFSET
1,1
COMMENTS
There are runs of three successive terms of A025487 that have an equal number of divisors. The smallest elements in these runs are 51840, 17149215283200, 63147292984115358771227840741376000000000, ... . Are there such runs of four successive terms?
LINKS
FORMULA
a(n) = A025487(A375195(n)).
EXAMPLE
6 is a term since 6 and 8 are two successive terms of A025487, and they have an equal number of divisors: A000005(6) = A000005(8) = 4.
MATHEMATICA
With[{lps = Cases[Import["https://oeis.org/A025487/b025487.txt", "Table"], {_, _}][[;; , 2]]}, lps[[Position[Differences[DivisorSigma[0, lps]], 0] // Flatten]]]
CROSSREFS
KEYWORD
nonn
AUTHOR
Amiram Eldar, Aug 04 2024
STATUS
approved