A250641 Number of length n+1 0..3 arrays with the sum of the maximum of each adjacent pair multiplied by some arrangement of +-1 equal to zero.

1, 36, 44, 476, 1424, 7696, 28238, 126482, 491943, 2059700, 8161068, 33268124, 132637221, 534771362, 2136620867, 8574987528, 34285733053, 137334914170, 549255340746, 2198311980408, 8792729559738, 35179581032056, 140715004320059

Offset: 1

Author

R. H. Hardin, Nov 26 2014

Keywords

• nonn

Comments

Column 3 of A250646

Examples

			Some solutions for n=6
..0....0....3....2....0....1....2....2....3....0....1....3....3....0....1....0
..2....3....2....3....0....0....3....2....1....3....2....2....1....3....1....1
..1....2....1....2....3....1....1....3....3....1....1....3....1....3....1....2
..2....2....1....0....0....1....0....2....3....3....1....0....1....1....3....0
..0....2....2....2....2....1....2....1....2....1....0....1....2....2....1....2
..2....0....3....2....2....3....1....3....1....3....1....1....1....0....0....1
..2....0....1....1....0....1....1....2....2....1....0....3....0....3....3....1
		

Links

• R. H. Hardin, Table of n, a(n) for n = 1..187

Formula

Empirical: a(n) = 11*a(n-1) -22*a(n-2) -172*a(n-3) +787*a(n-4) +353*a(n-5) -7413*a(n-6) +8289*a(n-7) +29140*a(n-8) -67796*a(n-9) -32276*a(n-10) +217716*a(n-11) -108368*a(n-12) -314968*a(n-13) +384528*a(n-14) +123824*a(n-15) -451104*a(n-16) +169760*a(n-17) +185424*a(n-18) -183216*a(n-19) +24640*a(n-20) +40064*a(n-21) -24448*a(n-22) +5760*a(n-23) -512*a(n-24) for n>25