A302383 Number of 4Xn 0..1 arrays with every element equal to 1, 2, 3 or 4 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.

0, 34, 475, 4640, 56541, 688999, 8334338, 100913905, 1222239033, 14803542454, 179291982859, 2171499466232, 26300156362525, 318534929264743, 3857942140993326, 46725546245979040, 565917413571325189

Offset

1,2

Comments

Row 4 of A302381.

Links

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

Formula

Empirical: a(n) = 7*a(n-1) +54*a(n-2) +84*a(n-3) +189*a(n-4) -346*a(n-5) -2353*a(n-6) -2331*a(n-7) -6761*a(n-8) -16996*a(n-9) -27532*a(n-10) -27887*a(n-11) -32208*a(n-12) -69423*a(n-13) +95849*a(n-14) -78017*a(n-15) +96046*a(n-16) +178129*a(n-17) -220388*a(n-18) +739594*a(n-19) -344706*a(n-20) +304213*a(n-21) +725099*a(n-22) -969680*a(n-23) +586777*a(n-24) -644301*a(n-25) -302444*a(n-26) +761784*a(n-27) -159825*a(n-28) +115661*a(n-29) -48119*a(n-30) -118870*a(n-31) +70352*a(n-32) +21347*a(n-33) -3527*a(n-34) +9495*a(n-35) +1159*a(n-36) -4509*a(n-37) +1182*a(n-38) +139*a(n-39) -373*a(n-40) -43*a(n-41) +24*a(n-42) for n>43

Example

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

Crossrefs

Cf. A302381.

Sequence in context: A107917 A277226 A241633 * A303104 A066291 A228682

Adjacent sequences: A302380 A302381 A302382 * A302384 A302385 A302386

Keyword

nonn

Author

R. H. Hardin, Apr 06 2018

Status

approved