cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

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A375196 Smaller of two successive terms of A025487 that have an equal number of divisors.

Original entry on oeis.org

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

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Author

Amiram Eldar, Aug 04 2024

Keywords

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?

Examples

			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.
		

Crossrefs

Programs

  • Mathematica
    With[{lps = Cases[Import["https://oeis.org/A025487/b025487.txt", "Table"], {, }][[;; , 2]]}, lps[[Position[Differences[DivisorSigma[0, lps]], 0] // Flatten]]]

Formula

a(n) = A025487(A375195(n)).
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