A301950 Number of nX7 0..1 arrays with every element equal to 1, 2 or 3 horizontally or antidiagonally adjacent elements, with upper left element zero.

8, 549, 23565, 1029960, 45013365, 1969215107, 86143630040, 3768464135104, 164856325277648, 7211859806584972, 315492435721284502, 13801638251948339606, 603771111706342632388, 26412774266222749814259

Offset

1,1

Comments

Column 7 of A301951.

Links

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

Formula

Empirical: a(n) = 64*a(n-1) -839*a(n-2) -5242*a(n-3) +147362*a(n-4) -153362*a(n-5) -9475658*a(n-6) +28777576*a(n-7) +318339402*a(n-8) -1185024188*a(n-9) -6711791018*a(n-10) +24015282348*a(n-11) +100290975324*a(n-12) -276220618432*a(n-13) -1092218614448*a(n-14) +1809378532768*a(n-15) +8381318969064*a(n-16) -5547141136292*a(n-17) -43048893696882*a(n-18) -5137214033550*a(n-19) +138723299981218*a(n-20) +103837461034320*a(n-21) -249665678213809*a(n-22) -352515712028408*a(n-23) +171279537015488*a(n-24) +541632747814928*a(n-25) +119479093580776*a(n-26) -378401338237562*a(n-27) -246736419083125*a(n-28) +88641851815866*a(n-29) +121670588033711*a(n-30) +6214746226660*a(n-31) -25619915739633*a(n-32) -4730140054470*a(n-33) +2873067267800*a(n-34) +639326441636*a(n-35) -187231673608*a(n-36) -34700853920*a(n-37) +6530040896*a(n-38) +743196096*a(n-39) -66946176*a(n-40) -16244992*a(n-41) +854016*a(n-42) +56320*a(n-43) for n>47

Example

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

Crossrefs

Cf. A301951.

Sequence in context: A174252 A181682 A248331 * A240300 A240432 A275932

Adjacent sequences: A301947 A301948 A301949 * A301951 A301952 A301953

Keyword

nonn

Author

R. H. Hardin, Mar 29 2018

Status

approved