A203358 Number of n X 4 binary arrays with every 1 immediately preceded by 0 to the left or above.

5, 61, 565, 5677, 55517, 547897, 5390325, 53087833, 522656405, 5146261573, 50669762053, 498898530085, 4912170264077, 48365462156161, 476208363192837, 4688768398640689, 46165815830098469, 454550623943557645

Offset: 1

Author

R. H. Hardin, Dec 31 2011

Keywords

• nonn

Comments

Column 4 of A203362.

Examples

			Some solutions for n=5:
..0..0..0..0....0..0..0..1....0..1..0..1....0..1..0..1....0..1..0..0
..0..0..0..1....0..1..0..0....1..0..0..1....0..1..1..0....0..1..1..0
..1..1..1..0....0..0..0..1....0..1..1..0....0..1..0..0....1..0..1..1
..0..1..0..0....0..0..0..0....0..0..0..1....1..0..0..1....0..0..0..1
..1..0..0..1....0..0..0..1....0..0..1..0....0..0..1..0....0..1..0..1
		

Links

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

Crossrefs

Cf. A203362.

Formula

Empirical: a(n) = 5*a(n-1) +42*a(n-2) +54*a(n-3) +23*a(n-4) -7*a(n-5).

Empirical g.f.: x*(5 + 36*x + 50*x^2 + 20*x^3 - 7*x^4) / (1 - 5*x - 42*x^2 - 54*x^3 - 23*x^4 + 7*x^5). - Colin Barker, Jun 04 2018