A194616 Half the number of lower triangles of a 3X3 0..n array with no element equal to the average of its horizontal and vertical neighbors

5, 96, 775, 3638, 12438, 34247, 82057, 175111, 344173, 630849, 1094898, 1812250, 2887675, 4445870, 6653357, 9703428, 13843860, 19356297, 26596343, 35955433, 47921851, 63027619, 81920692, 105300352, 134012453, 168951880, 211194991

Offset

1,1

Comments

Row 2 of A194615

Links

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

Formula

Empirical: a(n) = -a(n-1) +a(n-3) +2*a(n-4) +3*a(n-5) +3*a(n-6) +a(n-7) -2*a(n-8) -5*a(n-9) -6*a(n-10) -6*a(n-11) -2*a(n-12) +2*a(n-13) +5*a(n-14) +7*a(n-15) +6*a(n-16) +2*a(n-17) -2*a(n-18) -4*a(n-19) -4*a(n-20) -a(n-21) +a(n-22) +4*a(n-23) +4*a(n-24) +2*a(n-25) -2*a(n-26) -6*a(n-27) -7*a(n-28) -5*a(n-29) -2*a(n-30) +2*a(n-31) +6*a(n-32) +6*a(n-33) +5*a(n-34) +2*a(n-35) -a(n-36) -3*a(n-37) -3*a(n-38) -2*a(n-39) -a(n-40) +a(n-42) +a(n-43)

Example

Some solutions for n=2
..2......2......1......1......1......2......0......1......2......0......2
..0.2....1.0....0.2....0.2....2.2....0.2....2.0....0.2....0.2....1.0....1.1
..1.0.1..0.1.2..2.1.0..1.0.1..0.1.0..2.0.2..0.2.0..1.1.2..1.1.2..2.1.2..1.0.1

Crossrefs

Sequence in context: A192343 A152839 A266245 * A285367 A208253 A284664

Adjacent sequences: A194613 A194614 A194615 * A194617 A194618 A194619

Keyword

nonn

Author

R. H. Hardin Aug 30 2011

Status

approved