A253290 Number of (n+1)X(2+1) 0..2 arrays with every 2X2 subblock sum differing from its neighbors horizontally, vertically, diagonally and antidiagonally.

558, 3600, 23546, 167832, 1184928, 8243488, 57474376, 402165016, 2811886280, 19648735840, 137308874176, 959744819720, 6708131042848, 46884212361800, 327678437410752, 2290232105294136, 16007076725008072, 111877100758327680

Offset: 1

Author

R. H. Hardin, Dec 29 2014

Keywords

• nonn

Comments

Column 2 of A253294

Examples

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

Links

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

Formula

Empirical: a(n) = 4*a(n-1) +22*a(n-2) -47*a(n-3) +847*a(n-4) -2548*a(n-5) -14241*a(n-6) +46156*a(n-7) -235684*a(n-8) +513456*a(n-9) +3142562*a(n-10) -12248092*a(n-11) [phone]*a(n-12) -44225096*a(n-13) -327631492*a(n-14) [phone]*a(n-15) -3049192352*a(n-16) [phone]*a(n-17) [phone]*a(n-18) -67675653456*a(n-19) [phone]*a(n-20) -119547407360*a(n-21) -386660564160*a(n-22) [phone]*a(n-23) -2855898321408*a(n-24) [phone]*a(n-25) -381216535552*a(n-26) -12897724549120*a(n-27) [phone]*a(n-28) -73144228077568*a(n-29) [phone]*a(n-30) [phone]*a(n-31) -290876893462528*a(n-32) [phone]*a(n-33) -360592985554944*a(n-34) -244530708480000*a(n-35) +1126160419258368*a(n-36) -1315197520183296*a(n-37) -66806203023360*a(n-38) +1063245997670400*a(n-39) -489223618560000*a(n-40)