A241257 Number of 3Xn 0..3 arrays with no element equal to one plus the sum of elements to its left or zero plus the sum of the elements above it or one plus the sum of the elements diagonally to its northwest or zero plus the sum of the elements antidiagonally to its northeast, modulo 4

4, 17, 13, 34, 71, 135, 356, 734, 1705, 3914, 8291, 19714, 42700, 93528, 214479, 462299, 1030477, 2304077, 5035291, 11240675, 24870524, 54876698, 121998539, 269425049, 596725510, 1322494224, 2923575132, 6478965125, 14341026682

Offset

1,1

Comments

Row 3 of A241255

Links

R. H. Hardin, Table of n, a(n) for n = 1..202

Formula

Empirical: a(n) = 5*a(n-2) +12*a(n-3) -10*a(n-4) -49*a(n-5) -32*a(n-6) +99*a(n-7) +157*a(n-8) -89*a(n-9) -342*a(n-10) -104*a(n-11) +431*a(n-12) +412*a(n-13) -199*a(n-14) -494*a(n-15) -154*a(n-16) -16*a(n-17) +1491*a(n-18) +1405*a(n-19) -1976*a(n-20) -3729*a(n-21) -239*a(n-22) +1932*a(n-23) +2761*a(n-24) -1387*a(n-25) +1240*a(n-26) +884*a(n-27) -1768*a(n-28) -1322*a(n-29) +738*a(n-30) -734*a(n-31) -1142*a(n-32) -314*a(n-33) +2396*a(n-34) +196*a(n-35) -1802*a(n-36) +778*a(n-37) +1882*a(n-38) -1840*a(n-39) -1356*a(n-40) +744*a(n-41) -900*a(n-42) -560*a(n-43) +220*a(n-44) -104*a(n-45) -32*a(n-46) +244*a(n-47) +24*a(n-48) -72*a(n-49) +56*a(n-50) -24*a(n-52) for n>59

Example

Some solutions for n=4
..2..2..3..2....3..3..2..2....2..2..3..3....2..2..3..2....3..3..2..2
..0..0..0..3....2..1..3..1....0..0..2..1....0..0..0..3....2..1..3..1
..0..3..1..2....0..2..0..2....0..0..0..3....0..0..2..2....0..2..2..2

Crossrefs

Sequence in context: A264217 A341442 A063625 * A057596 A070712 A195884

Adjacent sequences: A241254 A241255 A241256 * A241258 A241259 A241260

Keyword

nonn

Author

R. H. Hardin, Apr 18 2014

Status

approved