A206006 Number of (n+1)X5 0..2 arrays with the number of clockwise edge increases in every 2X2 subblock equal to one, and every 2X2 determinant nonzero

722, 3706, 12068, 64224, 211824, 1159120, 3850160, 21563332, 71908620, 410324398, 1371057344, 7935278938, 26539793884, 155196079882, 519275349560, 3058687618974, 10235947682204, 60595706198366, 202797923521632

Offset

1,1

Comments

Column 4 of A206010

Links

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

Formula

Empirical: a(n) = 8*a(n-1) +42*a(n-2) -482*a(n-3) -293*a(n-4) +11440*a(n-5) -11229*a(n-6) -137742*a(n-7) +261810*a(n-8) +894760*a(n-9) -2462973*a(n-10) -2981208*a(n-11) +12607691*a(n-12) +3180168*a(n-13) -38516874*a(n-14) +11294550*a(n-15) +72866395*a(n-16) -51223616*a(n-17) -84265347*a(n-18) +98230578*a(n-19) +50978982*a(n-20) -112745308*a(n-21) +3184853*a(n-22) +82656280*a(n-23) -34966370*a(n-24) -37445012*a(n-25) +32301744*a(n-26) +8331808*a(n-27) -15845182*a(n-28) +649616*a(n-29) +4536888*a(n-30) -914656*a(n-31) -719464*a(n-32) +226432*a(n-33) +51024*a(n-34) -24320*a(n-35) -128*a(n-36) +1024*a(n-37) -128*a(n-38) for n>40

Example

Some solutions for n=4
..2..1..0..2..2....0..1..0..1..2....0..1..2..1..0....0..1..1..1..0
..0..1..1..1..2....1..1..1..1..1....1..1..1..1..1....1..1..2..1..1
..1..1..2..1..1....1..0..1..0..1....0..1..2..1..2....2..1..1..1..2
..1..2..2..2..0....1..1..1..1..1....1..1..1..1..1....1..1..0..1..1
..2..2..0..2..2....1..0..1..2..1....1..2..0..1..2....2..1..1..1..2

Crossrefs

Sequence in context: A260498 A259721 A133531 * A231485 A035756 A107552

Adjacent sequences: A206003 A206004 A206005 * A206007 A206008 A206009

Keyword

nonn

Author

R. H. Hardin Feb 02 2012

Status

approved