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Binary expansion matches ((0)*00(1*)11)*(0*).
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%I #15 Jan 01 2021 11:23:11

%S 0,3,6,7,12,14,15,24,28,30,31,48,51,56,60,62,63,96,99,102,103,112,115,

%T 120,124,126,127,192,195,198,199,204,206,207,224,227,230,231,240,243,

%U 248,252,254,255,384,387,390,391

%N Binary expansion matches ((0)*00(1*)11)*(0*).

%C In binary expansion, 1-bits occur only in groups of two or more, separated from other such groups by at least two 0-bits.

%C Integers that satisfy A048727(n) = 3*n.

%H <a href="/index/Con#CongruCrossDomain">Index entries for sequences defined by congruent products between domains N and GF(2)[X]</a>

%t filterQ[n_] := !MatchQ[IntegerDigits[n, 2], {1}|{1, 0, ___}|{___, 0, 1}|{___, 1, 0, 1, ___}|{___, 0, 1, 0, ___}];

%t Select[Range[0, 400], filterQ] (* _Jean-François Alcover_, Dec 31 2020 *)

%Y Row 3 of A115872. Superset of A048719. Cf. A048733.

%K nonn,base,easy

%O 0,2

%A _Antti Karttunen_, Mar 30 1999