A328992 - OEIS

%I #11 Nov 11 2019 13:49:08

%S 12,122121,1221212122121221,1221212122121221212212121221212212121221,

%T 12212121221212212122121212212122121212212122121212212122121221212122121221212122121221212212121221

%N a(0) = 12; thereafter a(n) is the concatenation of A328991(n),2,A328991(n-1).

%H Bill Allombert, Nicolas Brisebarre, and Alain Lasjaunias, <a href="https://arxiv.org/abs/1607.07235">On a two-valued sequence and related continued fractions in power series fields</a>, arXiv:1607.07235 [math.NT], 2016-2017; The Ramanujan Journal 45.3 (2018): 859-871. See U_n on page 863.

%Y Cf. A328991, A328993.

%K nonn

%O 0,1

%A _N. J. A. Sloane_, Nov 09 2019