A278268 Number of nX3 0..3 arrays with every element plus 1 mod 4 equal to some element at offset (-1,-1) (-1,0) (-1,1) (0,-1) (0,1) (1,-1) or (1,0), with upper left element zero.

0, 47, 1541, 46669, 1443372, 44653299, 1380961734, 42709293706, 1320881956427, 40851256530478, 1263417354853348, 39074034747765752, 1208452761189472245, 37374130557309864873, 1155879385419493659726, 35748180190801587747636

Offset

1,2

Comments

Column 3 of A278272.

Links

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

Formula

Empirical: a(n) = 36*a(n-1) -162*a(n-2) +228*a(n-3) -2482*a(n-4) +9972*a(n-5) -2070*a(n-6) +69586*a(n-7) -484397*a(n-8) +418362*a(n-9) -1615409*a(n-10) +16222445*a(n-11) -13260202*a(n-12) -86384152*a(n-13) +117435510*a(n-14) -54031926*a(n-15) +284670365*a(n-16) -3119976438*a(n-17) +20033186387*a(n-18) -26598585251*a(n-19) -52565516946*a(n-20) +106882788758*a(n-21) -76901072309*a(n-22) +323946214918*a(n-23) -469487165715*a(n-24) +290049469568*a(n-25) -683336099985*a(n-26) +523472975365*a(n-27) -100966982130*a(n-28) +168294869288*a(n-29) -106410454776*a(n-30) -67944547904*a(n-31) -12083149152*a(n-32) +13561255808*a(n-33) +23565683520*a(n-34) +7666456192*a(n-35) +1394460416*a(n-36) -327828480*a(n-37) -226152448*a(n-38) +42903552*a(n-39) +8224768*a(n-40)

Example

Some solutions for n=4
..0..1..0. .0..0..1. .0..1..0. .0..2..2. .0..1..1. .0..1..1. .0..1..1
..3..2..0. .1..2..0. .1..2..3. .1..3..1. .1..2..2. .0..2..1. .3..2..1
..2..3..2. .0..3..3. .0..3..1. .0..1..1. .1..3..3. .1..3..1. .2..0..2
..1..2..1. .1..2..2. .3..0..3. .3..2..0. .0..0..2. .0..3..2. .3..3..1

Crossrefs

Cf. A278272.

Sequence in context: A153214 A142845 A202128 * A014941 A280707 A324433

Adjacent sequences: A278265 A278266 A278267 * A278269 A278270 A278271

Keyword

nonn

Author

R. H. Hardin, Nov 16 2016

Status

approved