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%I #5 Mar 31 2012 12:36:16
%S 1,1,1,1,8,22,46,85,168,350,776,1787,3851,8141,17247,36921,79637,
%T 172237,371343,797047,1710188,3673435,7899653,16995309,36552835,
%U 78580754,168899252,363064232,780553896,1678245531,3608276813,7757481797
%N Number of permutations of 1..n with displacements restricted to {-4,0,1,2,3}
%H R. H. Hardin, <a href="/A189584/b189584.txt">Table of n, a(n) for n = 1..200</a>
%F Empirical: a(n) = a(n-1) +2*a(n-3) +2*a(n-4) +4*a(n-5) +10*a(n-6) +13*a(n-7) -3*a(n-8) +3*a(n-9) -11*a(n-10) +2*a(n-11) +5*a(n-12) -31*a(n-13) -11*a(n-14) -10*a(n-15) -3*a(n-16) +3*a(n-17) +a(n-18) -28*a(n-19) +22*a(n-20) -18*a(n-21) +10*a(n-22) -3*a(n-23) -8*a(n-24) +5*a(n-25) -4*a(n-26) -3*a(n-27) +2*a(n-28) +3*a(n-30) +2*a(n-31) -a(n-32) +a(n-33) +a(n-35)
%e Some solutions for n=11
%e ..1....5....5....5....5....5....5....5....1....1....5....5....5....1....5....5
%e ..2....1....2....2....1....6....1....1....6....2....1....2....2....6....1....1
%e ..7....3....1....3....2....1....3....2....3....7....2....1....1....2....2....2
%e ..3....4....3....1....8....3....8....8....4....3....3....4....8....3....4....3
%e ..5....2....4....9....3....2....2....3....2....5....9....3....3....5....9....9
%e .10...10...10....4....6...10....4....4...10...10...10...10....4....4....3...10
%e ..4....6....7...11....4....4...11....6...11....4....4...11...11...11...11....4
%e ..8....8....6....8....7....7....7....7....5....6....7....7....7....8....7....6
%e ..6....7....8....6....9....9....6....9....7....8....6....6....6....7....6....7
%e ..9....9....9....7...10....8....9...10....9....9....8....9....9...10....8....8
%e .11...11...11...10...11...11...10...11....8...11...11....8...10....9...10...11
%K nonn
%O 1,5
%A _R. H. Hardin_ Apr 24 2011
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