A270055 Number of nX5 0..4 arrays with some element plus some horizontally or vertically adjacent neighbor totalling four exactly once.

1280, 1683240, 1248460920, 779206497960, 446901694424400, 243724207420143600, 128543872461556329960, 66197363387248271149080, 33486151656718792957072320, 16705298615297314558207756320

Offset

1,1

Comments

Column 5 of A270058.

Links

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

Formula

Empirical: a(n) = 1084*a(n-1) -385060*a(n-2) +52207996*a(n-3) -3589359662*a(n-4) +139769030980*a(n-5) -3139297428484*a(n-6) +36970790802932*a(n-7) -109715789190473*a(n-8) -2264908466581072*a(n-9) +23041106193014144*a(n-10) -28405594469259904*a(n-11) -483359700838242304*a(n-12) +2011366933590159360*a(n-13) -2236659513127833600*a(n-14) for n>15

Example

Some solutions for n=1
..1..1..3..4..2. .0..4..1..1..4. .2..4..0..1..4. .1..2..2..3..0

Crossrefs

Cf. A270058.

Sequence in context: A090006 A170784 A269826 * A252116 A084803 A104399

Adjacent sequences: A270052 A270053 A270054 * A270056 A270057 A270058

Keyword

nonn

Author

R. H. Hardin, Mar 09 2016

Status

approved