A234055 Number of (1+2) X (n+2) 0..2 arrays with no increasing sequence of length 3 horizontally, diagonally downwards or antidiagonally downwards.

16488, 367857, 8226630, 184027176, 4114129859, 91973148874, 2055997586633, 45960182004045, 1027397134713634, 22966489726843437, 513393765537961480, 11476422031054555693, 256544314398972405775, 5734799925438397033971

Offset

1,1

Comments

Row 1 of A234054.

Links

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

Formula

Empirical: a(n) = 26*a(n-1) -2050*a(n-3) +3513*a(n-4) +37514*a(n-5) -38287*a(n-6) -146641*a(n-7) -648088*a(n-8) +422085*a(n-9) +6295334*a(n-10) -26687214*a(n-11) +42970321*a(n-12) +154270575*a(n-13) -296136092*a(n-14) +103796617*a(n-15) -592111595*a(n-16) -731932280*a(n-17) +1839743877*a(n-18) -1136679167*a(n-19) +1914973077*a(n-20) +3673514333*a(n-21) -4204799994*a(n-22) -980871943*a(n-23) -377031154*a(n-24) -1698215542*a(n-25) +2092098221*a(n-26) +520043633*a(n-27) -565923293*a(n-28) +27963876*a(n-29) +3578016*a(n-30) -237600*a(n-31) +3600*a(n-32).

Example

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

Crossrefs

Cf. A234054.

Sequence in context: A186848 A211841 A234054 * A234047 A223401 A281480

Adjacent sequences: A234052 A234053 A234054 * A234056 A234057 A234058

Keyword

nonn

Author

R. H. Hardin, Dec 19 2013

Status

approved