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%I #21 Nov 06 2017 09:36:16
%S 1,2,8,9,12,18,20,36,48,68,72,80,96,128,132,160,260,272,288,448,516,
%T 528,544,704,720,768,832,900,1025,1028,1040,1056,1152,1200,1216,1280,
%U 1296,1344,1536,1584,1600,2050,2052,2064,2080,2240,2352,2368,2448,2560,2624
%N A positive integer n is included if n and the number of divisors of n contain the same number of 1's in their binary representations.
%H Charles R Greathouse IV, <a href="/A162952/b162952.txt">Table of n, a(n) for n = 1..10000</a> (first 638 terms from Michael De Vlieger)
%e 20 has 6 divisors. 20 in binary is 10100, while 6 in binary is 110. Since both 10100 and 110 contain the same number of 1's (two 1's each), then 20 is in the sequence.
%p read("transforms") ; isA162952 := proc(n) RETURN( wt(n) = wt(numtheory[tau](n)) ) ; end: for n from 1 to 10000 do if isA162952(n) then printf("%d,",n) ; fi; od: # _R. J. Mathar_, Jul 30 2009
%t Select[Range[2^12], SameQ @@ DigitCount[{#, DivisorSigma[0, #]}, 2, 1] &] (* _Michael De Vlieger_, Nov 04 2017 *)
%o (PARI) isok(n) = (hammingweight(n) == hammingweight(numdiv(n))); \\ _Michel Marcus_, Nov 04 2017
%Y Cf. A162953.
%K base,nonn
%O 1,2
%A _Leroy Quet_, Jul 18 2009
%E Extended beyond a(10) by _R. J. Mathar_, Jul 30 2009
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