|
|
A303238
|
|
Number of nX4 0..1 arrays with every element equal to 0, 2, 3, 5 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.
|
|
1
|
|
|
1, 13, 8, 10, 61, 160, 458, 1748, 6056, 20975, 76565, 277934, 1007900, 3682461, 13473650, 49327443, 180826119, 663368564, 2434697476, 8939173919, 32829758366, 120594251282, 443046818432, 1627867352002, 5981695596761, 21981441331135
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,2
|
|
COMMENTS
|
|
|
LINKS
|
|
|
FORMULA
|
Empirical: a(n) = 6*a(n-1) -9*a(n-2) +21*a(n-3) -90*a(n-4) +46*a(n-5) -59*a(n-6) +498*a(n-7) +303*a(n-8) +2*a(n-9) -1395*a(n-10) -2312*a(n-11) -1830*a(n-12) +300*a(n-13) +2761*a(n-14) +3874*a(n-15) +8613*a(n-16) +16030*a(n-17) +21048*a(n-18) +7631*a(n-19) -27333*a(n-20) -67369*a(n-21) -75208*a(n-22) -16509*a(n-23) +47108*a(n-24) +59837*a(n-25) -35435*a(n-26) -119978*a(n-27) -82030*a(n-28) +115336*a(n-29) +248334*a(n-30) +137434*a(n-31) -175587*a(n-32) -360401*a(n-33) -165267*a(n-34) +287056*a(n-35) +566786*a(n-36) +354913*a(n-37) -61815*a(n-38) -419239*a(n-39) -359737*a(n-40) -69994*a(n-41) +152964*a(n-42) +111152*a(n-43) -23478*a(n-44) -121548*a(n-45) -86411*a(n-46) -6136*a(n-47) +64103*a(n-48) +63614*a(n-49) +31252*a(n-50) -324*a(n-51) -23046*a(n-52) -6881*a(n-53) +7713*a(n-54) +385*a(n-55) +2034*a(n-56) +2535*a(n-57) -1116*a(n-58) -2600*a(n-59) -1588*a(n-60) -112*a(n-61) +798*a(n-62) +676*a(n-63) -124*a(n-64) -253*a(n-65) -10*a(n-66) +66*a(n-67) +9*a(n-68) -13*a(n-69) -a(n-70) +a(n-71) for n>72
|
|
EXAMPLE
|
Some solutions for n=5
..0..1..0..1. .0..1..1..0. .0..0..1..0. .0..1..1..0. .0..0..0..1
..0..1..0..1. .0..1..1..1. .0..0..1..0. .1..1..1..0. .1..0..0..0
..0..1..0..1. .0..1..1..1. .0..0..1..0. .1..1..1..0. .0..0..0..0
..0..1..0..1. .0..1..1..0. .0..0..1..0. .0..0..1..1. .0..0..0..0
..0..1..0..1. .0..1..1..1. .0..0..1..0. .0..0..1..1. .1..0..0..1
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|