A295202 Number of n X 5 0..1 arrays with each 1 horizontally or vertically adjacent to 2 or 4 1's.

1, 6, 25, 108, 438, 1597, 5831, 21717, 81590, 307267, 1154956, 4332766, 16247319, 60941083, 228640675, 857901670, 3218928203, 12077227572, 45312279618, 170006395289, 637847836695, 2393151540417, 8978904610466, 33688073392021

Offset

1,2

Comments

Column 5 of A295205.

Links

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

Formula

Empirical: a(n) = 5*a(n-1) -7*a(n-2) +8*a(n-3) +16*a(n-5) -4*a(n-6) -71*a(n-7) +34*a(n-8) -123*a(n-9) -92*a(n-10) -94*a(n-11) +52*a(n-12) +370*a(n-13) +195*a(n-14) +622*a(n-15) +581*a(n-16) -286*a(n-17) -603*a(n-18) -1135*a(n-19) -627*a(n-20) +567*a(n-21) +347*a(n-22) +6*a(n-23) -217*a(n-24) -5*a(n-25) +32*a(n-26) -7*a(n-27) -7*a(n-28) -53*a(n-29) -6*a(n-30) +7*a(n-31) +2*a(n-32).

Example

Some solutions for n=7
..1..1..1..0..0. .0..0..0..0..0. .0..0..0..1..1. .1..1..1..1..0
..1..0..1..0..0. .1..1..0..0..0. .0..0..0..1..1. .1..0..0..1..1
..1..1..1..0..0. .1..1..1..1..0. .0..0..0..0..0. .1..0..0..0..1
..0..0..0..1..1. .0..1..0..1..1. .0..0..1..1..0. .1..1..0..0..1
..0..1..1..1..1. .0..1..0..0..1. .1..1..1..1..0. .0..1..0..0..1
..0..1..0..1..0. .0..1..1..1..1. .1..0..1..0..0. .0..1..1..0..1
..0..1..1..1..0. .0..0..0..0..0. .1..1..1..0..0. .0..0..1..1..1

Crossrefs

Cf. A295205.

Sequence in context: A147543 A212258 A048875 * A346894 A094669 A100296

Adjacent sequences: A295199 A295200 A295201 * A295203 A295204 A295205

Keyword

nonn

Author

R. H. Hardin, Nov 16 2017

Status

approved