A228216 Number of second differences of arrays of length n+2 of numbers in 0..6

25, 385, 4651, 47953, 439927, 3693505, 29066311, 219071473, 1609259287, 11658284065, 83824687591, 599858908753, 4277376525367, 30411820662145, 215703854542471, 1526853641242033, 10789535445362647, 76136107857549025

Offset

1,1

Comments

Column 6 of A228218

Links

R. H. Hardin, Table of n, a(n) for n = 1..64

Formula

Empirical: a(n) = 13*a(n-1) -42*a(n-2) for n>13

Example

Some solutions for n=4
..0...-7....0....3...-4....6....6....5....6....2...10...-7...-7....9..-10...-1
..0....1...-2....7....6....4....0...-8...-4...-6..-11....0...12...-4....8....3
..2...-4....5...-6...-8...-4...-9....7....3...-1....8....9...-7....0....0...-8
.-2....4...-7...-2....5....0....6...-6...-3....8...-5...-8....0....3...-2...12

Crossrefs

Sequence in context: A225968 A094190 A069396 * A261485 A125482 A306322

Adjacent sequences: A228213 A228214 A228215 * A228217 A228218 A228219

Keyword

nonn

Author

R. H. Hardin Aug 16 2013

Status

approved