cp's OEIS Frontend

A189588 Number of permutations of 1..n with displacements restricted to {-5,-4,-3,0,1,2}.

%I A189588 #7 Jun 02 2025 04:02:50
%S A189588 1,1,1,4,13,35,73,147,322,746,1758,4042,9114,20444,46217,105155,
%T A189588 239481,544259,1234420,2798863,6350149,14416419,32732101,74301920,
%U A189588 168633936,382715304,868630024,1971599952,4475144212,10157494573,23054646277
%N A189588 Number of permutations of 1..n with displacements restricted to {-5,-4,-3,0,1,2}.
%H A189588 R. H. Hardin, <a href="/A189588/b189588.txt">Table of n, a(n) for n = 1..200</a>
%F A189588 Empirical: a(n) = a(n-1) +2*a(n-3) +4*a(n-4) +7*a(n-5) +11*a(n-6) +14*a(n-7) +2*a(n-9) -14*a(n-10) -6*a(n-11) -8*a(n-12) -10*a(n-13) -10*a(n-14) -a(n-15) -3*a(n-16) +2*a(n-17) +a(n-20) +a(n-21)
%e A189588 Some solutions for n=10
%e A189588 ..1....1....1....1....5....1....6....6....4....1....4....1....1....1....4....5
%e A189588 ..7....6....2....2....1....7....2....1....1....2....5....2....5....2....2....2
%e A189588 ..8....3....6....3....8....2....1....2....2....6....1....6....3....3....1....1
%e A189588 ..2....2....3....9....2....4....8....8....8....3....2....4....2....4....3....8
%e A189588 ..3....4....5....4....3....3....3....3....3....4....3....3....9...10....5....3
%e A189588 ..4...10....4....5....4....5....4....4....5...10....9....9....4....5....9....4
%e A189588 ..5....5...10....6...10...10....5....5....6....5....6....5....6....6....6...10
%e A189588 ..6....7....7....7....6....6....7....7....7....7....8....7....7....7....7....6
%e A189588 ..9....8....8....8....7....9....9....9....9....9....7....8....8....9....8....7
%e A189588 .10....9....9...10....9....8...10...10...10....8...10...10...10....8...10....9
%K A189588 nonn
%O A189588 1,4
%A A189588 _R. H. Hardin_ Apr 24 2011