A181250 Number of n X 7 binary matrices with no 2 X 2 block having four 1's.

128, 11772, 1169792, 114142368, 11185495872, 1095020802848, 107224417436160, 10498818149889952, 1027999596778673856, 100657027683287334528, 9855884014448812881664, 965043721129265059674752

Offset: 1

Author

R. H. Hardin, Oct 10 2010

Keywords

• nonn

Comments

Column 7 of A181253.

Links

• R. H. Hardin, Table of n, a(n) for n=1..200

Crossrefs

Cf. A181253.

Formula

Empirical: a(n)=68*a(n-1)+3106*a(n-2)-10300*a(n-3)-731184*a(n-4)+3930848*a(n-5)[phone]*a(n-6)-471525808*a(n-7)[phone]*a(n-8)[phone]*a(n-9)-9445394304*a(n-10)-4382776896*a(n-11)[phone]*a(n-12)[phone]*a(n-13)-36065068032*a(n-14)-14871987200*a(n-15)[phone]*a(n-16)[phone]*a(n-17)-1119682560*a(n-18).