A075034 - OEIS

%I #29 Jul 10 2020 12:53:32

%S 20,21,32,33,44,45,56,57,75,80,81,84,85,92,93,104,105,116,117,132,135,

%T 140,141,144,147,165,170,171,176,177,189,200,201,204,212,213,216,217,

%U 224,225,230,231,242,243,252,260,261,272,285,296,297,300,301,315,324

%N Numbers n such that tau(n) >= tau(n+1) >= tau(n+2) where tau(n) = number of divisors of n.

%H Karl V. Keller, Jr., <a href="/A075034/b075034.txt">Table of n, a(n) for n = 1..10000</a>

%t nn = 400; t = DivisorSigma[0, Range[nn]]; Select[Range[nn-2], t[[#]] >= t[[#+1]] >= t[[#+2]] &] (* _Harvey P. Dale_, May 24 2012 *)

%o (Python)

%o from sympy import divisor_count as tau

%o [n for n in range(1,333) if tau(n) >= tau(n+1) >= tau(n+2)] # _Karl V. Keller, Jr._, Jul 10 2020

%Y Cf. A000005 (tau), A075032, A075033, A075035.

%K nonn

%O 1,1

%A _Amarnath Murthy_, Sep 02 2002

%E More terms from _Benoit Cloitre_, Sep 07 2002