A263697 - OEIS

%I #4 Oct 24 2015 06:44:07

%S 1,2,6,14,31,56,104,208,418,873,1772,3545,7103,14180,28572,57620,

%T 116055,233735,469754,944670,1900425,3823544,7695342,15483113,

%U 31150656,62671350,126083545,253679744,510398235,1026910104,2066113688,4156885969

%N Number of length n arrays of permutations of 0..n-1 with each element moved by -2 to 2 places and every three consecutive elements having its maximum within 4 of its minimum.

%C Column 2 of A263703.

%H R. H. Hardin, <a href="/A263697/b263697.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = a(n-1) +a(n-2) +7*a(n-5) +2*a(n-6) +a(n-7) +5*a(n-8) -4*a(n-9) -3*a(n-10) -3*a(n-11) -4*a(n-12) -4*a(n-14) -a(n-15) +3*a(n-16) -a(n-17) +a(n-19)

%e Some solutions for n=7

%e ..1....0....1....0....0....1....0....1....0....1....0....0....2....1....1....0

%e ..0....1....0....1....3....0....1....0....3....0....3....1....0....3....0....1

%e ..3....3....2....4....1....2....3....2....1....4....2....3....3....0....2....4

%e ..2....2....4....2....5....4....5....3....4....2....1....2....1....4....4....5

%e ..5....6....5....3....2....6....2....6....2....3....4....5....4....2....3....2

%e ..6....4....3....6....6....3....6....4....6....5....5....6....5....5....5....3

%e ..4....5....6....5....4....5....4....5....5....6....6....4....6....6....6....6

%Y Cf. A263703.

%K nonn

%O 1,2

%A _R. H. Hardin_, Oct 24 2015