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

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

Amiram Eldar, Table of n, a(n) for n = 1..4390

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

Cf. A000005, A025487, A146288, A375195.

Sequence in context: A337021 A262445 A090574 * A294842 A290132 A297713

Adjacent sequences: A375193 A375194 A375195 * A375197 A375198 A375200

Keyword

nonn

Author

Amiram Eldar, Aug 04 2024

Status

approved