A284071 Number of nX4 0..1 arrays with no 1 equal to more than three of its horizontal, diagonal and antidiagonal neighbors, with the exception of exactly two elements.

0, 6, 275, 7302, 151310, 2816826, 48994058, 812565760, 13024726520, 203381556682, 3110591645279, 46778444063114, 693678151593038, 10165365611526554, 147460852901201771, 2120338836015983926, 30254039436750997085

Offset

1,2

Comments

Column 4 of A284075.

Links

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

Formula

Empirical: a(n) = 33*a(n-1) -300*a(n-2) +32*a(n-3) +3402*a(n-4) +42147*a(n-5) -10398*a(n-6) -401499*a(n-7) -1778961*a(n-8) +1011851*a(n-9) +12805080*a(n-10) +30529581*a(n-11) -29629828*a(n-12) -172139721*a(n-13) -207374589*a(n-14) +353786001*a(n-15) +1034468307*a(n-16) +256346187*a(n-17) -2043653609*a(n-18) -2576319183*a(n-19) +2375745975*a(n-20) +5158025728*a(n-21) +132659427*a(n-22) -7795648047*a(n-23) -3605171554*a(n-24) +8489348817*a(n-25) +4142290659*a(n-26) -2903509566*a(n-27) -7496601300*a(n-28) +2314636680*a(n-29) +4513564645*a(n-30) -741508704*a(n-31) +62308878*a(n-32) -3600855885*a(n-33) +3595073904*a(n-34) -2476131675*a(n-35) +2635368007*a(n-36) -2197414518*a(n-37) +1423241388*a(n-38) -1023654655*a(n-39) +644059068*a(n-40) -329116782*a(n-41) +164011904*a(n-42) -70594374*a(n-43) +24735420*a(n-44) -7915920*a(n-45) +2073792*a(n-46) -405660*a(n-47) +55536*a(n-48) -5112*a(n-49) +288*a(n-50) -8*a(n-51)

Example

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

Crossrefs

Cf. A284075.

Sequence in context: A233234 A281694 A250390 * A254628 A211080 A288796

Adjacent sequences: A284068 A284069 A284070 * A284072 A284073 A284074

Keyword

nonn

Author

R. H. Hardin, Mar 19 2017

Status

approved