A364719 Numbers k such that d(k) > d(k+1) > d(k+2) > d(k+3), where d(n) is the number of divisors of n.

80, 224, 260, 440, 464, 476, 560, 594, 650, 714, 836, 860, 884, 980, 1016, 1088, 1184, 1280, 1376, 1520, 1700, 1862, 1904, 2024, 2060, 2096, 2444, 2450, 2816, 2870, 2960, 2996, 3020, 3024, 3164, 3200, 3320, 3380, 3450, 3620, 3800, 3944, 3968, 4004, 4130, 4136, 4250

Offset

1,1

Links

Seiichi Manyama, Table of n, a(n) for n = 1..10000

Mathematica

Flatten@Position[Differences@#&/@Partition[DivisorSigma[0, Range@5000], 4, 1], {_?(#<0&)..}] (* Hans Rudolf Widmer, Mar 11 2024 *)

Prog

(PARI) isok(n) = numdiv(n)>numdiv(n+1) && numdiv(n+1)>numdiv(n+2) && numdiv(n+2)>numdiv(n+3);

Crossrefs

Cf. A000005, A050944, A075029.

Cf. A074827, A364718, A364720.

Sequence in context: A044793 A359517 A211689 * A202439 A203355 A203348

Adjacent sequences: A364716 A364717 A364718 * A364720 A364721 A364722

Keyword

nonn,easy

Author

Seiichi Manyama, Aug 04 2023

Status

approved