A269034 Number of nX7 0..2 arrays with some element plus some horizontally, diagonally or antidiagonally adjacent neighbor totalling two exactly once.

576, 6912, 198816, 4998648, 119790816, 2783857776, 63310818360, 1416701634552, 31304407671636, 684763778434512, 14854833017622684, 320017408314705960, 6853471478780510820, 146027732878366085832, 3097663460112852295020

Offset

1,1

Comments

Column 7 of A269035.

Links

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

Formula

Empirical: a(n) = 82*a(n-1) -2779*a(n-2) +50254*a(n-3) -514677*a(n-4) +2743554*a(n-5) -2950648*a(n-6) -48609034*a(n-7) +245316224*a(n-8) -89432156*a(n-9) -2444502643*a(n-10) +5704858072*a(n-11) +7254972423*a(n-12) -41716035658*a(n-13) +18035762825*a(n-14) +132606292618*a(n-15) -178302990168*a(n-16) -171928095488*a(n-17) +491624257303*a(n-18) -70904009836*a(n-19) -621985038704*a(n-20) +477824279660*a(n-21) +281672875548*a(n-22) -522707244404*a(n-23) +119050620101*a(n-24) +190519380818*a(n-25) -140300285301*a(n-26) +10246766686*a(n-27) +24709126330*a(n-28) -9478840252*a(n-29) -368991021*a(n-30) +964165580*a(n-31) -172681320*a(n-32) -20355920*a(n-33) +9906636*a(n-34) -719568*a(n-35) -120720*a(n-36) +22272*a(n-37) -1024*a(n-38) for n>39

Example

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

Crossrefs

Cf. A269035.

Sequence in context: A325475 A268797 A036514 * A188787 A235738 A236078

Adjacent sequences: A269031 A269032 A269033 * A269035 A269036 A269037

Keyword

nonn

Author

R. H. Hardin, Feb 18 2016

Status

approved