A201091 Number of -n..n arrays of 6 elements with first and second differences also in -n..n.

89, 1653, 11817, 52401, 172767, 468159, 1100401, 2326467, 4525989, 8241301, 14210297, 23419633, 37141027, 56999737, 85011997, 123671261, 175984071, 245577021, 336727861, 454496567, 604748137, 794311497, 1030990023, 1323752505

Offset: 1

Author

R. H. Hardin Nov 26 2011

Keywords

• nonn

Comments

Row 6 of A201088

Examples

			Some solutions for n=4
..0...-4....1...-1....3....1....0....1....0....1....0...-1...-4....3....1....4
..3...-2....4....0....2...-1....0....0...-1....3....2....0...-4....1....2....1
..4....0....4...-1....2...-4...-2....0...-2....2....2....1...-2....0....2....0
..2....0....2...-2....3...-3...-2....0....1....3...-1....2...-2...-1....3....0
..1....1....2....0....2...-4...-2....2....1....2...-2....1...-1....1....4...-1
.-3....4....4....1....0...-2....2....0....0....4....0....1....2....3....1...-2
		

Links

• R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

Empirical: a(n) = 3*a(n-2) +2*a(n-3) -2*a(n-4) -5*a(n-5) -3*a(n-6) +a(n-7) +4*a(n-8) +6*a(n-9) +3*a(n-10) -3*a(n-11) -6*a(n-12) -4*a(n-13) -a(n-14) +3*a(n-15) +5*a(n-16) +2*a(n-17) -2*a(n-18) -3*a(n-19) +a(n-21)