A224151 Number of 7Xn 0..1 arrays with rows and antidiagonals unimodal and columns nondecreasing

8, 64, 357, 1536, 5471, 16885, 46586, 117510, 275557, 608423, 1277544, 2571226, 4991541, 9394324, 17211567, 30799955, 53979914, 92858530, 157069847, 261620888, 429605663, 696147855, 1114062432, 1761895136, 2755216271, 4262322913

Offset

1,1

Comments

Row 7 of A224146

Links

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

Formula

Empirical: a(n) = (1/87178291200)*n^14 + (1/4151347200)*n^13 + (1/136857600)*n^12 + (19/106444800)*n^11 + (53/12441600)*n^10 + (121/1382400)*n^9 + (1007857/609638400)*n^8 + (427321/29030400)*n^7 + (5519/62208)*n^6 + (217709/604800)*n^5 + (8736011/8553600)*n^4 + (1790117/950400)*n^3 + (90367957/37837800)*n^2 + (49717/40040)*n + 1

Example

Some solutions for n=3
..0..0..0....0..0..0....0..0..0....1..1..0....0..0..0....1..1..1....0..1..0
..0..1..0....0..0..0....0..0..0....1..1..1....0..1..0....1..1..1....0..1..0
..0..1..0....0..1..0....0..0..0....1..1..1....0..1..0....1..1..1....0..1..1
..0..1..0....0..1..1....0..0..0....1..1..1....0..1..0....1..1..1....0..1..1
..0..1..1....0..1..1....0..1..1....1..1..1....1..1..0....1..1..1....1..1..1
..0..1..1....0..1..1....0..1..1....1..1..1....1..1..0....1..1..1....1..1..1
..1..1..1....1..1..1....0..1..1....1..1..1....1..1..1....1..1..1....1..1..1

Crossrefs

Sequence in context: A267189 A181480 A223948 * A225014 A228460 A202909

Adjacent sequences: A224148 A224149 A224150 * A224152 A224153 A224154

Keyword

nonn

Author

R. H. Hardin Mar 31 2013

Status

approved