A300969 Number of nX4 0..1 arrays with every element equal to 1, 2, 3, 4 or 6 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.

2, 37, 459, 5362, 63565, 753471, 8926774, 105763972, 1253091915, 14846642172, 175903151550, 2084102123563, 24692460772840, 292556498411436, 3466212038154745, 41067711567915135, 486570617974927297

Offset

1,1

Comments

Column 4 of A300973.

Links

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

Formula

Empirical: a(n) = 16*a(n-1) -52*a(n-2) +28*a(n-3) +56*a(n-4) +123*a(n-5) -596*a(n-6) +202*a(n-7) +1114*a(n-8) +244*a(n-9) -3131*a(n-10) -352*a(n-11) +4162*a(n-12) +2026*a(n-13) -4839*a(n-14) -3744*a(n-15) +7609*a(n-16) +18297*a(n-17) -1782*a(n-18) -28845*a(n-19) -7069*a(n-20) +33095*a(n-21) +2775*a(n-22) -27095*a(n-23) -2505*a(n-24) +18334*a(n-25) +1817*a(n-26) -8564*a(n-27) -484*a(n-28) +3474*a(n-29) -1170*a(n-30) -1450*a(n-31) +1068*a(n-32) +757*a(n-33) -464*a(n-34) -280*a(n-35) +95*a(n-36) +80*a(n-37) -13*a(n-38) -12*a(n-39) +a(n-41) for n>42

Example

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

Crossrefs

Cf. A300973.

Sequence in context: A297796 A300542 A100849 * A120047 A300926 A337306

Adjacent sequences: A300966 A300967 A300968 * A300970 A300971 A300972

Keyword

nonn

Author

R. H. Hardin, Mar 17 2018

Status

approved