A302280 Number of 3 X n 0..1 arrays with every element equal to 1, 2 or 4 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.

0, 10, 22, 29, 74, 162, 363, 782, 1766, 3953, 8784, 19606, 43887, 98136, 219234, 490655, 1098086, 2457684, 5502261, 12323540, 27604374, 61847407, 138600898, 310664178, 696450255, 1561597724, 3502013800, 7854708637, 17619975144

Offset

1,2

Comments

Row 3 of A302278.

Links

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

Formula

Empirical: a(n) = 4*a(n-1) -4*a(n-2) +4*a(n-3) -7*a(n-4) -17*a(n-5) +29*a(n-6) -5*a(n-7) +24*a(n-8) +6*a(n-9) -75*a(n-10) +27*a(n-11) +16*a(n-12) +7*a(n-13) -8*a(n-14) -6*a(n-15) +6*a(n-16) for n>18

Example

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

Crossrefs

Cf. A302278.

Sequence in context: A303746 A303747 A007366 * A350627 A367918 A109958

Adjacent sequences: A302277 A302278 A302279 * A302281 A302282 A302283

Keyword

nonn

Author

R. H. Hardin, Apr 04 2018

Status

approved