A227749 Number of nX4 0,1 arrays indicating 2X2 subblocks of some larger (n+1)X5 binary array having determinant equal to one

13, 129, 1122, 10092, 90881, 817897, 7363367, 66282981, 596664236, 5371092567, 48349664362, 435235707529, 3917920494766, 35268475932174, 317481024485129, 2857912000299502, 25726454110486757, 231585311593846637

Offset

1,1

Comments

Column 4 of A227751

Links

R. H. Hardin, Table of n, a(n) for n = 1..133

Formula

Empirical: a(n) = a(n-1) +33*a(n-2) +232*a(n-3) +812*a(n-4) +1991*a(n-5) +3005*a(n-6) +2962*a(n-7) +599*a(n-8) -1449*a(n-9) +1224*a(n-10) +6483*a(n-11) +7495*a(n-12) -8986*a(n-13) -25763*a(n-14) -15443*a(n-15) +19185*a(n-16) +23662*a(n-17) -10225*a(n-18) -2280*a(n-19) +2949*a(n-20) -771*a(n-21) +4406*a(n-22) -3917*a(n-23) -2257*a(n-24) +483*a(n-25) +1552*a(n-26) -349*a(n-27) -456*a(n-28) +127*a(n-29) +91*a(n-30) -32*a(n-31) +4*a(n-32)

Example

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

Crossrefs

Sequence in context: A211897 A147669 A076457 * A016162 A155623 A023061

Adjacent sequences: A227746 A227747 A227748 * A227750 A227751 A227752

Keyword

nonn

Author

R. H. Hardin Jul 25 2013

Status

approved