A303527 Number of 4Xn 0..1 arrays with every element equal to 0, 1, 3, 4, 5 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.

8, 10, 39, 103, 359, 1875, 8676, 36072, 166784, 848681, 4105851, 19152575, 92409752, 457395652, 2221962919, 10661835678, 51739845297, 253006224877, 1229143772638, 5947176017011, 28886071524170, 140636912306075, 683180817411487

Offset

1,1

Comments

Row 4 of A303525.

Links

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

Formula

Empirical: a(n) = 3*a(n-1) +9*a(n-2) -3*a(n-3) +227*a(n-4) -651*a(n-5) -2397*a(n-6) +2477*a(n-7) -10125*a(n-8) +32889*a(n-9) +140430*a(n-10) -139247*a(n-11) +147713*a(n-12) -696247*a(n-13) -3322631*a(n-14) +2870371*a(n-15) -589928*a(n-16) +7378532*a(n-17) +37036533*a(n-18) -28171654*a(n-19) -4215822*a(n-20) -41705374*a(n-21) -201340805*a(n-22) +134959574*a(n-23) +48213202*a(n-24) +117390757*a(n-25) +527791613*a(n-26) -296182026*a(n-27) -143995072*a(n-28) -140279497*a(n-29) -728134284*a(n-30) +310394548*a(n-31) +146571481*a(n-32) +55671622*a(n-33) +702549436*a(n-34) -287100410*a(n-35) -94828128*a(n-36) +214598536*a(n-37) -403974010*a(n-38) -39173927*a(n-39) +37241894*a(n-40) +22203820*a(n-41) +40387406*a(n-42) -42016893*a(n-43) +45319265*a(n-44) -9357240*a(n-45) -14553359*a(n-46) +15173448*a(n-47) -2991486*a(n-48) -1107750*a(n-49) +1176217*a(n-50) -526881*a(n-51) +173233*a(n-52) -21811*a(n-53) -19352*a(n-54) +9547*a(n-55) -1989*a(n-56) +87*a(n-57) +18*a(n-58) for n>60

Example

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

Crossrefs

Cf. A303525.

Sequence in context: A303042 A242506 A302879 * A367893 A325999 A240036

Adjacent sequences: A303524 A303525 A303526 * A303528 A303529 A303530

Keyword

nonn

Author

R. H. Hardin, Apr 25 2018

Status

approved