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%I #5 Mar 31 2012 12:36:16
%S 1,1,2,4,13,26,62,132,274,614,1315,2955,6423,14058,30838,67170,147553,
%T 322304,706400,1546128,3382752,7408261,16208271,35489093,77672999,
%U 170021833,372181083,814611385,1783211187,3903138418,8543748906
%N Number of permutations of 1..n with displacements restricted to {-4,-2,0,1,3}
%H R. H. Hardin, <a href="/A189583/b189583.txt">Table of n, a(n) for n = 1..200</a>
%F Empirical: a(n) = a(n-1) +2*a(n-3) +3*a(n-4) +7*a(n-5) +25*a(n-7) -10*a(n-8) +7*a(n-9) -5*a(n-10) -23*a(n-11) -15*a(n-12) -4*a(n-13) -66*a(n-14) +23*a(n-15) -5*a(n-16) +16*a(n-17) +28*a(n-18) -14*a(n-19) +4*a(n-20) +55*a(n-21) -13*a(n-22) -7*a(n-23) -16*a(n-24) -8*a(n-25) +14*a(n-26) -2*a(n-27) -15*a(n-28) +a(n-30) +3*a(n-31) +a(n-32) -a(n-33) +a(n-35)
%e Some solutions for n=10
%e ..1....3....3....1....1....1....1....1....5....1....3....5....1....1....1....5
%e ..4....1....1....4....2....2....2....6....2....2....2....1....2....2....6....2
%e ..2....2....2....2....5....3....3....7....3....7....7....2....5....3....3....3
%e ..8....4....4....3....6....8....6....3....1....4....1....6....3....4....4....1
%e ..5....9....5....5....9....4....4....2....9....5....9....9....7....5....2....4
%e ..3....5....8....8....3....5....5....5....8....3....8....3....8....6....5....6
%e ..9....6....7....9....4....6....9....4....4....6....4....4....4....7....9....9
%e ..7...10...10....7....7....7...10...10...10....8....5....7...10...10...10...10
%e ..6....8....6....6....8....9....8....8....6....9....6....8....6....8....8....8
%e .10....7....9...10...10...10....7....9....7...10...10...10....9....9....7....7
%K nonn
%O 1,3
%A _R. H. Hardin_ Apr 24 2011
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