A203041 Number of (n+3) X 4 binary arrays with no more than one of any consecutive four bits set in any row or column.

209, 637, 2005, 6365, 19957, 62393, 195261, 612041, 1918365, 6011045, 18832757, 59007013, 184888993, 579320337, 1815187133, 5687517861, 17820706801, 55837720705, 174956625753, 548192325273, 1717653145453, 5381929652993

Offset

1,1

Comments

Column 1 of A203048.

Links

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

Formula

Empirical: a(n) = 2*a(n-1) + 2*a(n-2) + a(n-3) + 10*a(n-4) + 7*a(n-5) - 4*a(n-7) - a(n-8).

Empirical g.f.: x*(209 + 219*x + 313*x^2 + 872*x^3 + 490*x^4 - 89*x^5 - 313*x^6 - 73*x^7) / (1 - 2*x - 2*x^2 - x^3 - 10*x^4 - 7*x^5 + 4*x^7 + x^8). - Colin Barker, Jun 03 2018

Example

Some solutions for n=3:
  0 1 0 0    0 0 0 1    0 1 0 0    0 0 1 0    0 1 0 0
  0 0 0 1    0 1 0 0    0 0 0 0    0 0 0 0    1 0 0 0
  0 0 0 0    0 0 1 0    0 0 0 0    0 0 0 0    0 0 1 0
  0 0 0 0    0 0 0 0    0 0 0 0    0 1 0 0    0 0 0 1
  0 0 1 0    1 0 0 0    0 0 1 0    1 0 0 0    0 0 0 0
  0 0 0 1    0 0 0 0    0 0 0 1    0 0 1 0    1 0 0 0

Crossrefs

Cf. A203048.

Sequence in context: A316761 A260011 A203048 * A293981 A181623 A104874

Adjacent sequences: A203038 A203039 A203040 * A203042 A203043 A203044

Keyword

nonn

Author

R. H. Hardin, Dec 27 2011

Status

approved