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A164457
Number of binary strings of length n with no substrings equal to 0001, 0011, or 1010.
3
1, 2, 4, 8, 13, 21, 33, 52, 82, 128, 200, 313, 488, 761, 1188, 1852, 2887, 4503, 7020, 10943, 17063, 26601, 41468, 64652, 100792, 157128, 244965, 381898, 595363, 928166, 1446998, 2255827, 3516797, 5482628, 8547285, 13325053, 20773513, 32385456, 50488278
OFFSET
0,2
LINKS
Alois P. Heinz, Table of n, a(n) for n = 0..2000 (first 500 terms from R. H. Hardin)
FORMULA
G.f.: -(x^7-2*x^6+x^2+1)/((x-1)*(x^4-2*x^3-x+1)). - R. J. Mathar, Jan 19 2011
MATHEMATICA
LinearRecurrence[{2, -1, 2, -3, 1}, {1, 2, 4, 8, 13, 21, 33, 52}, 40] (* Harvey P. Dale, Aug 19 2022 *)
CROSSREFS
Sequence in context: A164429 A073336 A164420 * A164419 A164431 A164480
KEYWORD
nonn
AUTHOR
R. H. Hardin, Aug 14 2009
EXTENSIONS
Edited by Alois P. Heinz, Oct 12 2017
STATUS
approved