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%I #6 Jun 27 2012 13:57:06
%S 1,3,27,6943,1819024347,4000076419257964896255,
%T 77372730618755190082837640024229164347468807163,
%U 237146729315719909074685533605289611245100501015339264143038071525981840734161007646995989118658281471
%N An auxiliary bit-mask sequence for computing A066425. (The "dirty", unsymmetric one).
%H A. Karttunen, <a href="/A066425/a066425s.txt">Scheme functions for computing A066425 and related sequences.</a>
%F A068222(1)=1, A068222(n) = A068221(n) | (A068222(n-1) >> A068058(n-1)) [where | means bitwise or and >> is binary right shift]
%Y The corresponding "clean" bit-mask sequence is A068221. This sequence in binary: A068224. The width of these bit-masks is given by A068739. The position of the rightmost zero bit: A068058. The width of central gap of the term a(n), (n>1) is given by A068059(n-1)-1 = 0, 1, 3, 5, 10, 12, ... (i.e. partial sums of A068058).
%K nonn
%O 1,2
%A _Antti Karttunen_, Feb 26 2002