A302520 Number of 7Xn 0..1 arrays with every element equal to 0, 1, 4 or 5 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.

64, 22, 28, 163, 376, 1088, 4558, 23944, 95681, 344525, 1302832, 5550086, 23153940, 91082448, 353017903, 1418215128, 5785509156, 23250191623, 92140078093, 367162912762, 1476616246378, 5935545674594, 23726268173317, 94734366451064

Offset

1,1

Comments

Row 7 of A302515.

Links

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

Formula

Empirical: a(n) = a(n-1) +2*a(n-2) +5*a(n-3) +124*a(n-4) +113*a(n-5) +37*a(n-6) -47*a(n-7) -2901*a(n-8) -2868*a(n-9) +1875*a(n-10) +1261*a(n-11) +23265*a(n-12) +25593*a(n-13) -20268*a(n-14) -3073*a(n-15) -107075*a(n-16) -94478*a(n-17) +62944*a(n-18) -76347*a(n-19) +312669*a(n-20) +13413*a(n-21) -39205*a(n-22) +181202*a(n-23) -498359*a(n-24) +274119*a(n-25) -94414*a(n-26) -149744*a(n-27) +474263*a(n-28) -414929*a(n-29) +213390*a(n-30) +15865*a(n-31) -247470*a(n-32) +277066*a(n-33) -158702*a(n-34) +55846*a(n-35) +49720*a(n-36) -84556*a(n-37) +33873*a(n-38) -14054*a(n-39) -8001*a(n-40) +7808*a(n-41) -664*a(n-42) +901*a(n-43) +3003*a(n-44) +424*a(n-45) -703*a(n-46) -236*a(n-47) -92*a(n-48) -40*a(n-49) -4*a(n-50) for n>55

Example

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

Crossrefs

Cf. A302515.

Sequence in context: A303089 A302894 A303629 * A302685 A281721 A303319

Adjacent sequences: A302517 A302518 A302519 * A302521 A302522 A302523

Keyword

nonn

Author

R. H. Hardin, Apr 09 2018

Status

approved