[go: up one dir, main page]

login
A164434
Number of binary strings of length n with no substrings equal to 0000 0101 or 1010.
1
13, 23, 40, 70, 122, 213, 372, 650, 1135, 1982, 3462, 6047, 10561, 18445, 32216, 56268, 98275, 171643, 299787, 523599, 914499, 1597232, 2789674, 4872353, 8509886, 14863080, 25959362, 45339756, 79188896, 138308673, 241565308, 421909890, 736893690, 1287033861
OFFSET
4,1
FORMULA
G.f.: -x^4*(-13-10*x-17*x^2-4*x^3+7*x^4+12*x^5+8*x^6) / ( 1-x-2*x^3-x^4+x^6+x^7 ). - R. J. Mathar, Jan 19 2011
a(n) = a(n-1)+2*a(n-3)+a(n-4)-a(n-6)-a(n-7). - Wesley Ivan Hurt, May 20 2021
CROSSREFS
Sequence in context: A374102 A164416 A164491 * A164494 A164407 A259216
KEYWORD
nonn,easy
AUTHOR
R. H. Hardin Aug 14 2009
STATUS
approved