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Even numbers whose odd part is of the form 4m+3; Numbers missing from A241816.
4

%I #23 Aug 31 2024 04:27:50

%S 6,12,14,22,24,28,30,38,44,46,48,54,56,60,62,70,76,78,86,88,92,94,96,

%T 102,108,110,112,118,120,124,126,134,140,142,150,152,156,158,166,172,

%U 174,176,182,184,188,190,192,198,204,206,214,216,220,222,224,230,236

%N Even numbers whose odd part is of the form 4m+3; Numbers missing from A241816.

%C Numbers with bit-0 in their binary representation zero, and whose least significant 1-bit is neighbored (to the left) by another 1-bit, in other words, all even terms of A091067. - _Antti Karttunen_, Feb 20 2015

%C The asymptotic density of this sequence is 1/4. - _Amiram Eldar_, Aug 31 2024

%H Alois P. Heinz, <a href="/A246590/b246590.txt">Table of n, a(n) for n = 1..10000</a>

%F a(n) = 2*A091067(n). - _Antti Karttunen_, Feb 20 2015

%t Select[2 * Range[120], Mod[# / 2^IntegerExponent[#, 2], 4] == 3 &] (* _Amiram Eldar_, Aug 31 2024 *)

%o (PARI) is(k) = !(k % 2) && (k >> valuation(k, 2)) % 4 == 3; \\ _Amiram Eldar_, Aug 31 2024

%Y Complement of A241816.

%Y Cf. A091067.

%K nonn,base

%O 1,1

%A _N. J. A. Sloane_, Sep 03 2014

%E More terms from _Alois P. Heinz_, Sep 07 2014

%E New definition added to name by _Antti Karttunen_, Feb 20 2015