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Numbers k such that k is a member of A002183 but 2*k is not.
2

%I #13 Nov 13 2019 10:15:45

%S 1280,1600,4800,28672,131072,688128,6881280,7864320,39321600,43253760,

%T 94371840,201326592,528482304,9663676416,115964116992,241591910400,

%U 265751101440,347892350976,811748818944,3522410053632,4174708211712,21646635171840,23811298689024,27058293964800

%N Numbers k such that k is a member of A002183 but 2*k is not.

%H Amiram Eldar, <a href="/A160233/b160233.txt">Table of n, a(n) for n = 1..1000</a>

%e 1280 qualifies because 1280 is a member of A002183 but 1280*2 = 2560 is not.

%t (* capture the terms in the b002183.txt file: "Number of divisors of n-th highly composite number" and assign it to the variable 's' *) Select[ Take[s, 964], !MemberQ[s, 2 # ] &] (* _Robert G. Wilson v_, May 09 2009 *)

%Y Cf. A002182, A002183.

%K nonn

%O 1,1

%A _J. Lowell_, May 04 2009

%E More terms from _Robert G. Wilson v_, May 09 2009

%E More terms from _Amiram Eldar_, Nov 13 2019