A239180 Number of (2+1)X(n+1) 0..2 arrays with no element greater than all horizontal neighbors or equal to all vertical neighbors

12, 82, 514, 3358, 22396, 148820, 990458, 6592268, 43855688, 291663494, 1939766486, 12902228032, 85822416192, 570863549026, 3797126473142, 25256582287082, 167994557738914, 1117422617194994, 7432590319039134

Offset

1,1

Comments

Row 2 of A239178

Links

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

Formula

Empirical: a(n) = 9*a(n-1) -30*a(n-2) +86*a(n-3) +25*a(n-4) +182*a(n-5) +437*a(n-6) +536*a(n-7) +1051*a(n-8) -5283*a(n-9) -3524*a(n-10) -4115*a(n-11) -8861*a(n-12) +28896*a(n-13) +22724*a(n-14) -27014*a(n-15) -3080*a(n-16) -931*a(n-17) -15313*a(n-18) +16851*a(n-19) +3650*a(n-20) -10094*a(n-21) +3499*a(n-22) +1512*a(n-23) -867*a(n-24) +322*a(n-25) -565*a(n-26) -199*a(n-27) +54*a(n-28) -40*a(n-29) +15*a(n-30) -2*a(n-31)

Example

Some solutions for n=5
..0..0..2..2..2..1....0..0..0..2..2..0....0..0..0..1..1..0....2..2..2..2..2..0
..2..2..1..0..0..0....2..2..1..1..1..1....1..2..2..2..2..2....1..1..0..1..1..1
..0..0..2..2..2..2....0..0..2..2..2..0....0..0..1..1..0..0....0..0..1..2..2..2

Crossrefs

Sequence in context: A194493 A163020 A164300 * A290715 A175037 A252179

Adjacent sequences: A239177 A239178 A239179 * A239181 A239182 A239183

Keyword

nonn

Author

R. H. Hardin, Mar 11 2014

Status

approved