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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. 1
64, 22, 28, 163, 376, 1088, 4558, 23944, 95681, 344525, 1302832, 5550086, 23153940, 91082448, 353017903, 1418215128, 5785509156, 23250191623, 92140078093, 367162912762, 1476616246378, 5935545674594, 23726268173317, 94734366451064 (list; graph; refs; listen; history; text; internal format)
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

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Last modified February 18 09:15 EST 2020. Contains 332011 sequences. (Running on oeis4.)