login
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.
1
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
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
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jun 01 2018
STATUS
approved