A302325 Number of 4Xn 0..1 arrays with every element equal to 0, 1, 2 or 4 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.

8, 81, 281, 953, 3559, 14022, 55727, 218945, 863315, 3440917, 13790826, 55318042, 222174413, 894490623, 3609079051, 14580970526, 58964739319, 238673570964, 966918646489, 3919864249187, 15899457324900, 64518777918726

Offset

1,1

Comments

Row 4 of A302322.

Links

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

Formula

Empirical: a(n) = 15*a(n-1) -84*a(n-2) +178*a(n-3) +212*a(n-4) -2124*a(n-5) +5269*a(n-6) -3510*a(n-7) -17782*a(n-8) +58832*a(n-9) -63504*a(n-10) -34777*a(n-11) +238070*a(n-12) -503595*a(n-13) +483969*a(n-14) +380322*a(n-15) -1784881*a(n-16) +2885550*a(n-17) -2388299*a(n-18) -2044710*a(n-19) +8508331*a(n-20) -11069640*a(n-21) +6484882*a(n-22) +7814399*a(n-23) -23937227*a(n-24) +24744757*a(n-25) -8770039*a(n-26) -17134504*a(n-27) +36991911*a(n-28) -30236995*a(n-29) +6289056*a(n-30) +18222888*a(n-31) -30552741*a(n-32) +21644939*a(n-33) -5928173*a(n-34) -8448247*a(n-35) +15861968*a(n-36) -11557208*a(n-37) +5135768*a(n-38) +2731821*a(n-39) -6378730*a(n-40) +3495647*a(n-41) -2416045*a(n-42) -175726*a(n-43) +2217206*a(n-44) -844338*a(n-45) +548408*a(n-46) -120262*a(n-47) -541952*a(n-48) +200352*a(n-49) -45224*a(n-50) +12896*a(n-51) +69488*a(n-52) -22848*a(n-53) -3840*a(n-54) +3200*a(n-55) -4864*a(n-56) +1536*a(n-57) for n>58

Example

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

Crossrefs

Cf. A302322.

Sequence in context: A302417 A227227 A303184 * A303018 A247536 A302822

Adjacent sequences: A302322 A302323 A302324 * A302326 A302327 A302328

Keyword

nonn

Author

R. H. Hardin, Apr 05 2018

Status

approved