A221067 Sum of neighbor maps: number of nX3 binary arrays indicating the locations of corresponding elements equal to the sum mod 4 of their king-move neighbors in a random 0..3 nX3 array

8, 20, 512, 4096, 26976, 262144, 2097152, 16401664, 134217728, 1073741824, 8572235776, 68719476736, 549755813888, 4397319143424, 35184372088832, 281474976710656, 2251771635433472, 18014398509481984, 144115188075855872

Offset

1,1

Comments

Column 3 of A221072

Links

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

Formula

Empirical: a(n) = 8*a(n-1) +160*a(n-3) -1280*a(n-4) -11200*a(n-6) +89600*a(n-7) +453632*a(n-9) -3629056*a(n-10) -11841536*a(n-12) +94732288*a(n-13) +209715200*a(n-15) -1677721600*a(n-16) -2577661952*a(n-18) +20621295616*a(n-19) +22041067520*a(n-21) -176328540160*a(n-22) -128781910016*a(n-24) +1030255280128*a(n-25) +490700013568*a(n-27) -3925600108544*a(n-28) -1099511627776*a(n-30) +8796093022208*a(n-31) +1099511627776*a(n-33) -8796093022208*a(n-34)

Example

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

Crossrefs

Sequence in context: A214905 A230987 A060668 * A217018 A108235 A130021

Adjacent sequences: A221064 A221065 A221066 * A221068 A221069 A221070

Keyword

nonn

Author

R. H. Hardin Dec 31 2012

Status

approved