A318544 Number of nX7 0..1 arrays with every element unequal to 0, 1, 4 or 6 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.

21, 26, 107, 516, 2349, 10496, 46165, 208159, 942764, 4213744, 18870716, 84794983, 380556843, 1707239770, 7660779072, 34376713801, 154258564357, 692193258418, 3106040446532, 13937625995076, 62541652378393, 280640300310752

Offset

1,1

Comments

Column 7 of A318545.

Links

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

Formula

Empirical: a(n) = a(n-1) +46*a(n-3) +50*a(n-4) +275*a(n-5) -43*a(n-6) +362*a(n-7) -1637*a(n-8) -271*a(n-9) -3396*a(n-10) +3146*a(n-11) +3432*a(n-12) +6889*a(n-13) +7881*a(n-14) -20207*a(n-15) -21749*a(n-16) +31606*a(n-17) -30087*a(n-18) -43803*a(n-19) +168405*a(n-20) +76348*a(n-21) -293820*a(n-22) -123142*a(n-23) +290600*a(n-24) +147574*a(n-25) -215762*a(n-26) -149500*a(n-27) +261780*a(n-28) +316118*a(n-29) -671671*a(n-30) -764286*a(n-31) +1504462*a(n-32) +1206660*a(n-33) -2414304*a(n-34) -1168911*a(n-35) +2765306*a(n-36) +641957*a(n-37) -2226787*a(n-38) -174104*a(n-39) +1245814*a(n-40) +84501*a(n-41) -498990*a(n-42) -153476*a(n-43) +165047*a(n-44) +149749*a(n-45) -57567*a(n-46) -84000*a(n-47) +18254*a(n-48) +31251*a(n-49) -1064*a(n-50) -8936*a(n-51) -2803*a(n-52) +2260*a(n-53) +1619*a(n-54) -469*a(n-55) -485*a(n-56) +34*a(n-57) +95*a(n-58) +23*a(n-59) -11*a(n-60) -8*a(n-61) +a(n-63) for n>64

Example

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

Crossrefs

Cf. A318545.

Sequence in context: A134935 A344978 A299594 * A173836 A064507 A249729

Adjacent sequences: A318541 A318542 A318543 * A318545 A318546 A318547

Keyword

nonn

Author

R. H. Hardin, Aug 28 2018

Status

approved