A303199 Number of 4Xn 0..1 arrays with every element equal to 0, 1, 3, 5 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.

8, 10, 23, 46, 97, 283, 687, 1642, 3949, 10169, 25010, 60900, 149264, 373120, 920574, 2259062, 5562698, 13784985, 34019145, 83759406, 206523981, 510324559, 1259274155, 3104524302, 7657989177, 18904333224, 46644705875, 115050987507

Offset

1,1

Comments

Row 4 of A303197.

Links

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

Formula

Empirical: a(n) = a(n-1) +3*a(n-2) +2*a(n-3) +28*a(n-4) -31*a(n-5) -90*a(n-6) -44*a(n-7) -283*a(n-8) +376*a(n-9) +1008*a(n-10) +311*a(n-11) +1386*a(n-12) -2347*a(n-13) -6108*a(n-14) -872*a(n-15) -3347*a(n-16) +8856*a(n-17) +23769*a(n-18) -123*a(n-19) +1195*a(n-20) -22117*a(n-21) -64764*a(n-22) +7147*a(n-23) +19461*a(n-24) +38840*a(n-25) +127932*a(n-26) -21682*a(n-27) -74830*a(n-28) -50864*a(n-29) -183540*a(n-30) +36739*a(n-31) +157510*a(n-32) +54333*a(n-33) +187390*a(n-34) -42853*a(n-35) -222777*a(n-36) -53364*a(n-37) -129121*a(n-38) +39540*a(n-39) +223618*a(n-40) +49370*a(n-41) +50470*a(n-42) -32833*a(n-43) -162219*a(n-44) -37859*a(n-45) +76*a(n-46) +24074*a(n-47) +85250*a(n-48) +21014*a(n-49) -12817*a(n-50) -13251*a(n-51) -31994*a(n-52) -7827*a(n-53) +7830*a(n-54) +4713*a(n-55) +8220*a(n-56) +1874*a(n-57) -2410*a(n-58) -960*a(n-59) -1329*a(n-60) -278*a(n-61) +404*a(n-62) +95*a(n-63) +116*a(n-64) +24*a(n-65) -33*a(n-66) -3*a(n-67) -4*a(n-68) -a(n-69) +a(n-70) for n>71

Example

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

Crossrefs

Cf. A303197.

Sequence in context: A216047 A032488 A102844 * A097543 A088034 A182405

Adjacent sequences: A303196 A303197 A303198 * A303200 A303201 A303202

Keyword

nonn

Author

R. H. Hardin, Apr 19 2018

Status

approved