A234389 Number of (n+2)X(1+2) 0..3 arrays with no increasing sequence of length 3 horizontally or diagonally downwards

196316, 9292808, 426876528, 19562241288, 893326493316, 40779627244572, 1860744623018290, 84899953913483407, 3873501429344049400, 176724495756544758956, 8062812768583455896334, 367854389640020762312297

Offset

1,1

Comments

Column 1 of A234393

Links

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

Formula

Empirical: a(n) = 56*a(n-1) -26586*a(n-3) +161889*a(n-4) +3740796*a(n-5) -30895097*a(n-6) -187582514*a(n-7) +2012131719*a(n-8) +3280745010*a(n-9) -59781770178*a(n-10) +7670618556*a(n-11) +904843980967*a(n-12) -892611508774*a(n-13) -7204612789531*a(n-14) +10892252119424*a(n-15) +28238885649127*a(n-16) -56684455395140*a(n-17) -35741928894200*a(n-18) +126732346860892*a(n-19) -78600993413254*a(n-20) -49070875873290*a(n-21) +298655389117913*a(n-22) -293555658109466*a(n-23) -337785457906071*a(n-24) +667877163621548*a(n-25) +51130515043723*a(n-26) -819092825116086*a(n-27) +288447456035056*a(n-28) +623846568417000*a(n-29) -349481101559952*a(n-30) -250500894094540*a(n-31) +143930821969264*a(n-32) +59962044402386*a(n-33) -10651618650630*a(n-34) -25341728141720*a(n-35) +5021619526216*a(n-36) +951607924424*a(n-37) -672240236280*a(n-38) +347138677736*a(n-39) -70314891768*a(n-40) +4321472928*a(n-41) +870029888*a(n-42) -350580992*a(n-43) +45079552*a(n-44)

Example

Some solutions for n=1
..1..1..3....1..1..1....2..1..1....1..1..3....1..3..0....1..2..3....1..3..2
..2..3..0....0..0..0....0..0..3....1..1..0....0..3..1....1..2..0....3..2..3
..0..2..3....3..3..1....3..2..3....2..2..0....2..3..1....3..0..1....3..0..0

Crossrefs

Sequence in context: A309190 A074388 A234996 * A234393 A234394 A202434

Adjacent sequences: A234386 A234387 A234388 * A234390 A234391 A234392

Keyword

nonn

Author

R. H. Hardin, Dec 25 2013

Status

approved