A269051 Number of nX7 0..2 arrays with some element plus some horizontally, diagonally or antidiagonally adjacent neighbor totalling two not more than once.

768, 9864, 253416, 6053094, 140497512, 3193266318, 71430596250, 1577976495486, 34509932303172, 748499855355192, 16122334931683590, 345226129034011068, 7354858033380328494, 156000244649213353110, 3296017711974478218258

Offset: 1

Author

R. H. Hardin, Feb 18 2016

Keywords

• nonn

Comments

Column 7 of A269052.

Examples

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

Links

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

Crossrefs

Cf. A269052.

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) [phone]*a(n-8) -89432156*a(n-9) -2444502643*a(n-10) [phone]*a(n-11) [phone]*a(n-12) -41716035658*a(n-13) [phone]*a(n-14) [phone]*a(n-15) -178302990168*a(n-16) -171928095488*a(n-17) [phone]*a(n-18) -70904009836*a(n-19) -621985038704*a(n-20) [phone]*a(n-21) [phone]*a(n-22) -522707244404*a(n-23) [phone]*a(n-24) [phone]*a(n-25) -140300285301*a(n-26) [phone]*a(n-27) [phone]*a(n-28) -9478840252*a(n-29) -368991021*a(n-30) [phone]*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