A080240 Define two sequences by A_n = mex{A_i,B_i : 0 <= i < n} for n >= 0, B_0=0, B_1=1 and for n >= 2, B_n = 2B_{n-1}+(-1)^{A_n}. Sequence gives A_n.

0, 1, 2, 4, 5, 6, 8, 9, 10, 11, 12, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76

Offset

0,3

Comments

The minimal excluded value of set of nonnegative numbers S is mex S = least nonnegative integer not in S.

The sequence B_n is given in A080241.

Links

Table of n, a(n) for n=0..71.

A. S. Fraenkel, Home Page

A. S. Fraenkel, New games related to old and new sequences, INTEGERS, Electronic J. of Combinatorial Number Theory, Vol. 4, Paper G6, 2004.

Crossrefs

Cf. A080241.

Sequence in context: A172284 A039242 A039185 * A345443 A135668 A276216

Adjacent sequences: A080237 A080238 A080239 * A080241 A080242 A080243

Keyword

nonn

Author

Aviezri S. Fraenkel, Mar 12 2003

Extensions

More terms from Emeric Deutsch, Apr 13 2005

Status

approved