A302227 - OEIS

A302227

Number of 4Xn 0..1 arrays with every element equal to 1, 2 or 3 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.

0, 34, 194, 934, 6110, 38736, 251254, 1610569, 10296766, 66243864, 424625879, 2726394062, 17497812841, 112298621494, 720825717366, 4626342158809, 29694255667486, 190589162278017, 1223278644711981, 7851527608519228

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OFFSET

1,2

COMMENTS

Row 4 of A302224.

LINKS

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

FORMULA

Empirical: a(n) = 2*a(n-1) +46*a(n-2) -788*a(n-4) -646*a(n-5) +6434*a(n-6) +6201*a(n-7) -28548*a(n-8) -19144*a(n-9) +59264*a(n-10) -8209*a(n-11) +97963*a(n-12) +207006*a(n-13) -1098204*a(n-14) -507314*a(n-15) +3485081*a(n-16) +276950*a(n-17) -5506599*a(n-18) +473443*a(n-19) +2482943*a(n-20) +506556*a(n-21) +8109563*a(n-22) -4109434*a(n-23) -21303483*a(n-24) +5376215*a(n-25) +28671693*a(n-26) -135719*a(n-27) -26171138*a(n-28) -6896727*a(n-29) +15548107*a(n-30) +8991124*a(n-31) -3953690*a(n-32) -5343561*a(n-33) -1641633*a(n-34) +576769*a(n-35) +1453672*a(n-36) +1139326*a(n-37) -138815*a(n-38) -702483*a(n-39) -125657*a(n-40) +244637*a(n-41) +55357*a(n-42) -68301*a(n-43) -34287*a(n-44) +3547*a(n-45) +16186*a(n-46) +4392*a(n-47) -3502*a(n-48) -1602*a(n-49) +56*a(n-50) +268*a(n-51) +140*a(n-52) -16*a(n-53) -16*a(n-54) for n>58

EXAMPLE

Some solutions for n=5

..0..0..0..0..0. .0..1..1..1..1. .0..1..1..1..0. .0..1..1..0..0

..1..1..1..1..0. .0..0..1..0..0. .0..0..1..0..1. .0..0..1..0..0

..0..0..0..0..1. .1..0..1..0..0. .1..0..1..0..0. .1..0..1..0..0

..0..1..1..1..1. .0..1..0..1..1. .1..1..0..0..0. .0..1..1..1..0

CROSSREFS

Cf. A302224.

Sequence in context: A200256 A074709 A074900 * A058581 A050263 A020869

Adjacent sequences: A302224 A302225 A302226 * A302228 A302229 A302230

KEYWORD

nonn

AUTHOR

R. H. Hardin, Apr 03 2018

STATUS

approved