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1,2
Also a(n) = (1/2)*s(n), where s(n) is the n-th even number in A026166.
Table of n, a(n) for n=1..63.
F. M. Dekking, Permutations of N generated by left-right filling algorithms, arXiv:2001.08915 [math.CO], 2020.
Cf. A026166, A026136.
Sequence in context: A105529 A329454 A120237 * A026198 A026206 A117606
Adjacent sequences: A026179 A026180 A026181 * A026183 A026184 A026185
nonn
Clark Kimberling
Edited by N. J. A. Sloane, Jan 31 2020
approved