A328993 a(0) = 2; thereafter a(n) is the concatenation 2,A328991(n).

2, 21, 21221, 212212121221, 21221212122121221212212121221, 2122121212212122121221212122121221212122121221212122121221212212121221

Offset

0,1

Links

Table of n, a(n) for n=0..5.

Bill Allombert, Nicolas Brisebarre, and Alain Lasjaunias, On a two-valued sequence and related continued fractions in power series fields, arXiv:1607.07235 [math.NT], 2016-2017; The Ramanujan Journal 45.3 (2018): 859-871. See V_n on page 863.

Crossrefs

Cf. A328991, A328992.

Sequence in context: A201973 A278737 A162393 * A336768 A180700 A077526

Adjacent sequences: A328990 A328991 A328992 * A328994 A328995 A328996

Keyword

nonn

Author

N. J. A. Sloane, Nov 10 2019

Status

approved