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%I #23 Nov 27 2020 04:51:12
%S 6,8,10,12,14,15,18,20,21,22,24,26,27,28,30,32,33,34,35,36,38,39,40,
%T 42,44,45,46,48,50,51,52,54,55,56,57,58,60,62,63,64,65,66,68,69,70,72,
%U 74,75,76,77,78,80,82,84,85,86,87,88,90,91,92,93,94,95,96,98,99,100,102,104,105,106,108,110,111,112,114,115,116,117,118,119,120
%N "Fermi-Dirac composites": numbers k for which A064547(k) > 1.
%H Antti Karttunen, <a href="/A268388/b268388.txt">Table of n, a(n) for n = 1..10000</a>
%e 6 = 2^1 * 3^1 is present, as there are altogether two 1-bits in the exponents (1 and 1 also in binary), which is more than one.
%e 64 = 2^6 is present, as the binary representation of 6 is "110", which contains more than one 1-bit. This is also the first term not present in A139118.
%t Select[Range[120], Plus @@ DigitCount[Last /@ FactorInteger[#], 2, 1] > 1 &] (* _Amiram Eldar_, Nov 27 2020 *)
%o (Scheme, with _Antti Karttunen_'s IntSeq-library)
%o (define A268388 (MATCHING-POS 1 1 (lambda (n) (> (A064547 n) 1))))
%o (PARI) isok(n) = my(f = factor(n)[,2]); sum(k=1, #f, hammingweight(f[k])) > 1; \\ _Michel Marcus_, Feb 10 2016
%Y Subsequence of A002808.
%Y Cf. A050376 (complement without 1).
%Y Cf. A064547.
%Y Cf. A176699 (subsequence), A000379 (also subsequence, without the initial 1).
%Y Different from A139118.
%K nonn
%O 1,1
%A _Antti Karttunen_, Feb 09 2016, after _Vladimir Shevelev_'s Apr 2010 comment in A176699.
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