A200371 Number of 0..n arrays x(0..8) of 9 elements with zero 3rd differences

2, 3, 4, 5, 6, 7, 8, 11, 14, 21, 28, 35, 42, 49, 60, 75, 90, 105, 120, 139, 162, 185, 208, 233, 262, 295, 328, 365, 402, 447, 492, 541, 590, 639, 692, 757, 822, 887, 952, 1027, 1102, 1185, 1268, 1355, 1450, 1549, 1648, 1751, 1858, 1973, 2092, 2219, 2346, 2473, 2608

Offset

1,1

Comments

Row 4 of A200370

Links

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

Formula

Empirical: a(n) = -a(n-2) -a(n-4) -a(n-6) -a(n-8) +a(n-15) +a(n-16) +a(n-17) +a(n-18) +a(n-19) +a(n-20) +2*a(n-21) +a(n-22) +2*a(n-23) +a(n-24) +a(n-25) +a(n-27) +a(n-28) +a(n-29) +a(n-30) -a(n-31) +a(n-32) -a(n-33) +a(n-34) -a(n-35) -2*a(n-37) -a(n-38) -2*a(n-39) -a(n-40) -a(n-41) -a(n-42) -2*a(n-43) -2*a(n-44) -2*a(n-45) -a(n-46) -a(n-47) -a(n-48) -2*a(n-49) -a(n-50) -2*a(n-51) -a(n-53) +a(n-54) -a(n-55) +a(n-56) -a(n-57) +a(n-58) +a(n-59) +a(n-60) +a(n-61) +a(n-63) +a(n-64) +2*a(n-65) +a(n-66) +2*a(n-67) +a(n-68) +a(n-69) +a(n-70) +a(n-71) +a(n-72) +a(n-73) -a(n-80) -a(n-82) -a(n-84) -a(n-86) -a(n-88)

Example

Some solutions for n=10
..1....5....8....3....4....6....9...10....0....8...10....2....6....0....0....9
..1....5....7....3....4....6....9....9....4....8...10....2....3....0....1....8
..1....5....6....3....4....6....9....8....7....8...10....2....1....0....2....7
..1....5....5....3....4....6....9....7....9....8...10....2....0....0....3....6
..1....5....4....3....4....6....9....6...10....8...10....2....0....0....4....5
..1....5....3....3....4....6....9....5...10....8...10....2....1....0....5....4
..1....5....2....3....4....6....9....4....9....8...10....2....3....0....6....3
..1....5....1....3....4....6....9....3....7....8...10....2....6....0....7....2
..1....5....0....3....4....6....9....2....4....8...10....2...10....0....8....1

Crossrefs

Sequence in context: A258946 A008815 A298434 * A246025 A211699 A118600

Adjacent sequences: A200368 A200369 A200370 * A200372 A200373 A200374

Keyword

nonn

Author

R. H. Hardin Nov 16 2011

Status

approved