A269293 Number of 5Xn 0..3 arrays with some element plus some horizontally or antidiagonally adjacent neighbor totalling three no more than once.

1024, 314928, 43674876, 5306911092, 598478857956, 64538382287988, 6751724437907820, 691013309706097812, 69557358002931376452, 6911040753656957427300, 679500524238978108503340

Offset: 1

Author

R. H. Hardin, Feb 21 2016

Keywords

• nonn

Comments

Row 5 of A269289.

Examples

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

Links

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

Crossrefs

Cf. A269289.

Formula

Empirical: a(n) = 262*a(n-1) -25913*a(n-2) +1271424*a(n-3) -36373480*a(n-4) [phone]*a(n-5) -8018113210*a(n-6) [phone]*a(n-7) -356568260410*a(n-8) [phone]*a(n-9) -1609856308508*a(n-10) -4162483461884*a(n-11) [phone]*a(n-12) -40474763971218*a(n-13) [phone]*a(n-14) [phone]*a(n-15) -171480164894532*a(n-16) [phone]*a(n-17) -29562621871104*a(n-18) for n>23