%I #19 Mar 11 2024 13:41:03
%S 80,224,260,440,464,476,560,594,650,714,836,860,884,980,1016,1088,
%T 1184,1280,1376,1520,1700,1862,1904,2024,2060,2096,2444,2450,2816,
%U 2870,2960,2996,3020,3024,3164,3200,3320,3380,3450,3620,3800,3944,3968,4004,4130,4136,4250
%N 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.
%H Seiichi Manyama, <a href="/A364719/b364719.txt">Table of n, a(n) for n = 1..10000</a>
%t Flatten@Position[Differences@#&/@Partition[DivisorSigma[0,Range@5000],4,1], {_?(#<0&)..}] (* _Hans Rudolf Widmer_, Mar 11 2024 *)
%o (PARI) isok(n) = numdiv(n)>numdiv(n+1) && numdiv(n+1)>numdiv(n+2) && numdiv(n+2)>numdiv(n+3);
%Y Cf. A000005, A050944, A075029.
%Y Cf. A074827, A364718, A364720.
%K nonn,easy
%O 1,1
%A _Seiichi Manyama_, Aug 04 2023
|