A305448 Number of nX4 0..1 arrays with every element unequal to 1, 2, 4, 5 or 8 king-move adjacent elements, with upper left element zero.

2, 10, 20, 26, 169, 475, 1234, 5007, 16422, 51196, 182859, 619558, 2064945, 7171550, 24597409, 83961318, 290423638, 1002057750, 3452837246, 11953834123, 41373636357, 143157425820, 496258006589, 1720526318696, 5965062389328

Offset

1,1

Comments

Column 4 of A305452.

Links

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

Formula

Empirical: a(n) = 3*a(n-1) +5*a(n-2) +38*a(n-3) -148*a(n-4) -218*a(n-5) -519*a(n-6) +2884*a(n-7) +3905*a(n-8) +3339*a(n-9) -30562*a(n-10) -39086*a(n-11) -11324*a(n-12) +205212*a(n-13) +247611*a(n-14) +21938*a(n-15) -946170*a(n-16) -1056076*a(n-17) -58020*a(n-18) +3157175*a(n-19) +3127065*a(n-20) +410332*a(n-21) -7983337*a(n-22) -6503680*a(n-23) -2165557*a(n-24) +16028242*a(n-25) +9483450*a(n-26) +6988788*a(n-27) -26528034*a(n-28) -9599746*a(n-29) -14430143*a(n-30) +36550764*a(n-31) +6751097*a(n-32) +19453991*a(n-33) -41014953*a(n-34) -3830421*a(n-35) -16581030*a(n-36) +35888878*a(n-37) +3500239*a(n-38) +6795491*a(n-39) -22738990*a(n-40) -5319082*a(n-41) +2956273*a(n-42) +8693110*a(n-43) +6173762*a(n-44) -6526618*a(n-45) -492143*a(n-46) -4460003*a(n-47) +4375118*a(n-48) -1220728*a(n-49) +1893599*a(n-50) -1415837*a(n-51) +478409*a(n-52) -386792*a(n-53) +165762*a(n-54) -41280*a(n-55) +17066*a(n-56) +9967*a(n-57) -2758*a(n-58) +2235*a(n-59) -1720*a(n-60) -212*a(n-61) -32*a(n-62) -64*a(n-63) for n>65

Example

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

Crossrefs

Cf. A305452.

Sequence in context: A307254 A293725 A351552 * A177150 A165551 A139592

Adjacent sequences: A305445 A305446 A305447 * A305449 A305450 A305451

Keyword

nonn

Author

R. H. Hardin, Jun 01 2018

Status

approved