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%I #7 Apr 16 2023 20:22:39
%S 1,1,2,4,10,29,67,130,276,618,1351,3003,6743,14819,32330,71269,157307,
%T 346284,763698,1684996,3710825,8172131,18012691,39696783,87466867,
%U 192761407,424805801,936047353,2062639546,4545431460,10016441028
%N Number of permutations of 1..n with displacements restricted to {-4,-1,0,2,3}.
%H R. H. Hardin, <a href="/A189582/b189582.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) +3*a(n-5) +11*a(n-6) +20*a(n-7) -5*a(n-8) +12*a(n-9) +4*a(n-10) -7*a(n-11) -13*a(n-12) -11*a(n-13) -48*a(n-14) +27*a(n-15) -38*a(n-16) -20*a(n-17) -21*a(n-18) +27*a(n-19) +13*a(n-20) +44*a(n-21) -25*a(n-22) +20*a(n-23) +2*a(n-24) +11*a(n-25) -15*a(n-26) -7*a(n-27) -12*a(n-28) +5*a(n-29) -2*a(n-30) -a(n-32) +a(n-33) +a(n-34) +a(n-35).
%e Some solutions for n=10
%e ..2....2....1....5....1....1....2....5....1....1....2....1....1....2....2....1
%e ..3....6....6....3....2....2....3....6....2....3....6....2....6....3....6....3
%e ..4....3....4....4....4....7....7....4....3....7....7....3....3....1....3....4
%e ..1....1....2....1....5....4....1....1....8....2....1....4....2....4....1....8
%e ..9....9....3....2....3....3....9....2....6....6....5....9....5....6....9....2
%e ..7....4...10...10...10...10....4....3....4...10....3...10....4...10....4....7
%e ..8....8....5....8....8....5....8....8....5....4....4....7....8....8....8....5
%e ..5....5....8....9....9....6....5....9....9....5....8....5....9....5....5....6
%e ..6...10....9....6....6....9....6...10....7....9....9....6...10....9....7....9
%e .10....7....7....7....7....8...10....7...10....8...10....8....7....7...10...10
%K nonn
%O 1,3
%A _R. H. Hardin_, Apr 24 2011
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