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A201349 Number of nX4 0..1 arrays with rows and columns lexicographically nondecreasing and every element equal to at least one horizontal or vertical neighbor 1
3, 14, 47, 191, 752, 2732, 9111, 28011, 79918, 213153, 535318, 1274359, 2892516, 6291669, 13172108, 26642251, 52229342, 99517435, 184747946, 334871408, 593751872, 1031516926, 1758440929, 2945277335, 4852655894, 7873078897 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 4 of A201353

LINKS

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

FORMULA

Empirical: a(n) = (1/1307674368000)*n^15 - (1/87178291200)*n^14 + (19/7472424960)*n^13 - (61/958003200)*n^12 + (48277/14370048000)*n^11 - (293/3483648)*n^10 + (787333/365783040)*n^9 - (24368131/609638400)*n^8 + (200509627/326592000)*n^7 - (316559651/43545600)*n^6 + (9499836221/143700480)*n^5 - (53265620347/119750400)*n^4 + (19358243050561/9081072000)*n^3 - (1030835612797/151351200)*n^2 + (36972827/2860)*n - 10961 for n>4

EXAMPLE

Some solutions for n=9

..0..0..0..1....0..0..0..1....0..0..0..1....0..0..1..1....0..0..0..0

..0..0..0..1....0..0..0..1....0..0..0..1....0..0..1..1....0..0..0..0

..0..1..1..1....0..0..1..1....0..0..0..1....0..1..0..1....0..0..0..0

..0..1..1..1....0..1..1..1....0..1..1..1....0..1..0..1....0..0..1..1

..1..0..0..1....1..0..0..1....1..0..0..0....1..0..0..0....0..0..1..1

..1..0..1..0....1..1..0..1....1..0..1..0....1..0..0..1....1..1..0..1

..1..0..1..0....1..1..0..1....1..0..1..0....1..0..0..1....1..1..0..1

..1..0..1..1....1..1..1..1....1..1..0..1....1..0..1..1....1..1..0..1

..1..1..1..1....1..1..1..1....1..1..0..1....1..1..1..1....1..1..1..1

CROSSREFS

Sequence in context: A202144 A287426 A246149 * A006900 A212505 A024453

Adjacent sequences:  A201346 A201347 A201348 * A201350 A201351 A201352

KEYWORD

nonn

AUTHOR

R. H. Hardin Nov 30 2011

STATUS

approved

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Last modified October 15 09:22 EDT 2019. Contains 328026 sequences. (Running on oeis4.)