

A164426


Number of binary strings of length n with no substrings equal to 0000 0011 or 0101.


1



13, 21, 34, 53, 81, 124, 188, 282, 422, 630, 936, 1387, 2053, 3033, 4473, 6591, 9704, 14274, 20983, 30832, 45283, 66481, 97576, 143181, 210054, 308108, 451874, 662642, 971620, 1424557, 2088498, 3061702, 4488192, 6579052, 9643637, 14135346
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OFFSET

4,1


LINKS



FORMULA

G.f.: x^4*(138*x13*x^2+7*x^3+14*x^4+12*x^5+8*x^6) / ( (x^3+x1)*(x^4+x^31) ).  R. J. Mathar, Dec 01 2011
a(n) = a(n1) + 2*a(n3)  a(n5)  a(n6)  a(n7).  Wesley Ivan Hurt, Aug 19 2022


MATHEMATICA

LinearRecurrence[{1, 0, 2, 0, 1, 1, 1}, {13, 21, 34, 53, 81, 124, 188}, 40] (* Harvey P. Dale, Feb 06 2019 *)


CROSSREFS



KEYWORD

nonn


AUTHOR



STATUS

approved



