A164144 Number of binary strings of length n with equal numbers of 001 and 101 substrings

1, 2, 4, 6, 8, 11, 18, 36, 76, 153, 289, 525, 954, 1787, 3464, 6832, 13452, 26207, 50603, 97525, 188805, 367994, 720805, 1414179, 2772486, 5428759, 10626469, 20818945, 40850896, 80275617, 157897960, 310707852, 611510788, 1203795095, 2370700373

Offset

0,2

Comments

Seems to obey an 8-term hypergeometric recurrence with cubic polynomial coefficients. - R. J. Mathar, Nov 28 2011.

Links

R. H. Hardin, Table of n, a(n) for n=0..500

Shalosh B. Ekhad and Doron Zeilberger, Automatic Solution of Richard Stanley's Amer. Math. Monthly Problem #11610 and ANY Problem of That Type, arXiv preprint arXiv:1112.6207, 2011. See subpages for rigorous derivations of g.f., recurrence, asymptotics for this sequence. [From N. J. A. Sloane, Apr 07 2012]

Crossrefs

Sequence in context: A039823 A284617 A079972 * A353007 A071241 A247123

Adjacent sequences: A164141 A164142 A164143 * A164145 A164146 A164147

Keyword

nonn

Author

R. H. Hardin Aug 11 2009

Status

approved