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%I #17 Mar 25 2020 10:51:18
%S 1,1,2,4,7,12,21,36,62,108,188,326,565,980,1700,2949,5116,8875,15395,
%T 26705,46325,80360,139400,241816,419476,727661,1262267,2189644,
%U 3798357,6588977,11429841,19827246,34394152,59663238,103497303,179535876
%N Number of permutations of 1..n with displacements restricted to {-6,-5,-4,-3,-2,0,1}.
%C a(n+1) is the number of multus bitstrings of length n with no runs of 7 ones. - _Steven Finch_, Mar 25 2020
%H R. H. Hardin, <a href="/A189593/b189593.txt">Table of n, a(n) for n = 1..200</a>
%H Steven Finch, <a href="https://arxiv.org/abs/2003.09458">Cantor-solus and Cantor-multus distributions</a>, arXiv:2003.09458 [math.CO], 2020.
%F Empirical: a(n) = a(n-1) +a(n-3) +a(n-4) +a(n-5) +a(n-6) +a(n-7).
%F Empirical g.f.: x*(1 + x^2)*(1 + x^3 + x^4) / ((1 - x + x^2)*(1 - x^2 - 2*x^3 - 2*x^4 - x^5)). - _Colin Barker_, May 02 2018
%e Some solutions for n=14:
%e ..1....4....3....1....4....5....1....1....3....1....1....4....1....1....1....3
%e ..5....1....1....5....1....1....5....7....1....2....2....1....5....4....7....1
%e ..2....2....2....2....2....2....2....2....2....5....7....2....2....2....2....2
%e ..3....3....4....3....3....3....3....3....4....3....3....3....3....3....3....4
%e ..4....8....7....4....5....4....4....4...10....4....4....5....4....5....4....7
%e ..6....5....5....6....6....6...11....5....5....8....5...10....6....9....5....5
%e ..7....6....6...10....7....7....6....6....6....6....6....6...11....6....6....6
%e .10....7...10....7....8...11....7....8....7....7....8....7....7....7....8...12
%e ..8....9....8....8...13....8....8....9....8...13....9....8....8....8....9....8
%e ..9...14....9....9....9....9....9...10....9....9...14....9....9...14...12....9
%e .13...10...11...11...10...10...10...11...14...10...10...11...10...10...10...10
%e .11...11...14...14...11...14...14...14...11...11...11...12...12...11...11...11
%e .12...12...12...12...12...12...12...12...12...12...12...13...13...12...13...13
%e .14...13...13...13...14...13...13...13...13...14...13...14...14...13...14...14
%K nonn
%O 1,3
%A _R. H. Hardin_, Apr 24 2011
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