A303193 Number of nX4 0..1 arrays with every element equal to 0, 1, 3, 5 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.

5, 17, 23, 46, 185, 497, 1357, 4207, 12167, 34473, 102325, 299504, 863917, 2529911, 7401255, 21512919, 62790998, 183429084, 534568781, 1559375192, 4551720900, 13275818353, 38726475676, 113002176247, 329660705673, 961703508351

Offset

1,1

Comments

Column 4 of A303197.

Links

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

Formula

Empirical: a(n) = 2*a(n-1) +2*a(n-2) +12*a(n-3) -16*a(n-4) -31*a(n-5) -40*a(n-6) +26*a(n-7) +53*a(n-8) +50*a(n-9) +35*a(n-10) +7*a(n-11) +a(n-12) -66*a(n-13) +111*a(n-14) +160*a(n-15) -144*a(n-16) -293*a(n-17) -37*a(n-18) +236*a(n-19) -90*a(n-20) -395*a(n-21) -6*a(n-22) +127*a(n-23) -242*a(n-24) -440*a(n-25) -17*a(n-26) +448*a(n-27) +310*a(n-28) +44*a(n-29) +97*a(n-30) +113*a(n-31) -8*a(n-32) -125*a(n-33) -100*a(n-34) -26*a(n-35) -a(n-36) +15*a(n-37) +10*a(n-38) +9*a(n-39) -a(n-41) -a(n-42) for n>43

Example

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

Crossrefs

Cf. A303197.

Sequence in context: A154632 A236119 A141275 * A145043 A097434 A106012

Adjacent sequences: A303190 A303191 A303192 * A303194 A303195 A303196

Keyword

nonn

Author

R. H. Hardin, Apr 19 2018

Status

approved