A189582 Number of permutations of 1..n with displacements restricted to {-4,-1,0,2,3}.

1, 1, 2, 4, 10, 29, 67, 130, 276, 618, 1351, 3003, 6743, 14819, 32330, 71269, 157307, 346284, 763698, 1684996, 3710825, 8172131, 18012691, 39696783, 87466867, 192761407, 424805801, 936047353, 2062639546, 4545431460, 10016441028

Offset: 1

Author

R. H. Hardin, Apr 24 2011

Keywords

• nonn

Examples

			Some solutions for n=10
..2....2....1....5....1....1....2....5....1....1....2....1....1....2....2....1
..3....6....6....3....2....2....3....6....2....3....6....2....6....3....6....3
..4....3....4....4....4....7....7....4....3....7....7....3....3....1....3....4
..1....1....2....1....5....4....1....1....8....2....1....4....2....4....1....8
..9....9....3....2....3....3....9....2....6....6....5....9....5....6....9....2
..7....4...10...10...10...10....4....3....4...10....3...10....4...10....4....7
..8....8....5....8....8....5....8....8....5....4....4....7....8....8....8....5
..5....5....8....9....9....6....5....9....9....5....8....5....9....5....5....6
..6...10....9....6....6....9....6...10....7....9....9....6...10....9....7....9
.10....7....7....7....7....8...10....7...10....8...10....8....7....7...10...10
		

Links

• R. H. Hardin, Table of n, a(n) for n = 1..200

Formula

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).