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A139373 Let the binary expansion of n be n = Sum_{k} 2^{r_k}, let e(n) be the number of r_k's that are even, o(n) the number that are odd; sequence lists n such that e(n) > o(n). 9

%I #11 Dec 15 2018 20:44:43

%S 1,4,5,7,13,16,17,19,20,21,22,23,25,28,29,31,37,49,52,53,55,61,64,65,

%T 67,68,69,70,71,73,76,77,79,80,81,82,83,84,85,86,87,88,89,91,92,93,94,

%U 95,97,100,101,103,109,112,113,115,116,117,118,119,121,124

%N Let the binary expansion of n be n = Sum_{k} 2^{r_k}, let e(n) be the number of r_k's that are even, o(n) the number that are odd; sequence lists n such that e(n) > o(n).

%C e(n)+o(n) = A000120(n), the binary weight of n. For e(n) = o(n) see A039004.

%t aQ[n_] := Module[{d = Reverse[IntegerDigits[n,2]]}, Total@d[[1;;-1;;2]] > Total@d[[2;;-1;;2]]]; Select[Range[180], aQ] (* _Amiram Eldar_, Dec 15 2018 *)

%o See link in A139351 for Fortran program.

%o (PARI) isok(n) = {my(irb = Vec(select(x->(x%2), Vecrev(binary(n)), 1))); #select(x->(x%2), irb) > #irb/2;} \\ _Michel Marcus_, Dec 15 2018

%Y Cf. A000120, A139351, A139352, A139353, A139354, A139355.

%Y Cf. A039004, A139370, A139371, A139372.

%K nonn

%O 1,2

%A _Nadia Heninger_ and _N. J. A. Sloane_, Jun 07 2008

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