A099248 - OEIS

%I #25 Jul 16 2023 02:12:14

%S 3,7,9,10,12,15,31,33,34,35,36,37,38,39,40,41,42,43,44,45,46,48,49,50,

%T 51,52,53,54,56,57,58,60,63,127,129,130,132,135,136,139,141,142,144,

%U 147,149,150,153,154,156,159,160,163,165,166,169,170,172,175,177,178,180

%N Numbers such that length in binary representation and number of ones have a common divisor greater than 1.

%H Reinhard Zumkeller, <a href="/A099248/b099248.txt">Table of n, a(n) for n = 1..10000</a> (first 1810 terms from Diana Mecum)

%H <a href="/index/Bi#binary">Index entries for sequences related to binary expansion of n</a>.

%F A099244(a(n)) > 1.

%t Select[Range[200], !CoprimeQ[BitLength[#], DigitCount[#, 2, 1]] &] (* _Amiram Eldar_, Jul 16 2023 *)

%o (Haskell)

%o a099248 n = a099248_list !! (n-1)

%o a099248_list = filter ((> 1) . a099244) [1..]

%o -- _Reinhard Zumkeller_, Oct 10 2013

%Y Complement of A099247.

%Y Cf. A000120, A007088, A070939, A099244.

%K nonn,base

%O 1,1

%A _Reinhard Zumkeller_, Oct 08 2004

%E Corrected by _Leroy Quet_, Sep 04 2008

%E a(34) and beyond from _Diana L. Mecum_, Jan 04 2009