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A250428 Number of (n+1)X(4+1) 0..1 arrays with nondecreasing sum of every two consecutive values in every row and column 1
144, 720, 3600, 12000, 40000, 105000, 275625, 617400, 1382976, 2765952, 5531904, 10160640, 18662400, 32076000, 55130625, 89842500, 146410000, 228399600, 356303376, 535927392, 806105664, 1175570760, 1714374025, 2434614000 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 4 of A250432

LINKS

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

FORMULA

Empirical: a(n) = 2*a(n-1) +8*a(n-2) -18*a(n-3) -27*a(n-4) +72*a(n-5) +48*a(n-6) -168*a(n-7) -42*a(n-8) +252*a(n-9) -252*a(n-11) +42*a(n-12) +168*a(n-13) -48*a(n-14) -72*a(n-15) +27*a(n-16) +18*a(n-17) -8*a(n-18) -2*a(n-19) +a(n-20)

Empirical for n mod 2 = 0: a(n) = (1/147456)*n^10 + (23/73728)*n^9 + (13/2048)*n^8 + (77/1024)*n^7 + (1763/3072)*n^6 + (4525/1536)*n^5 + (5927/576)*n^4 + (3473/144)*n^3 + (145/4)*n^2 + (63/2)*n + 12

Empirical for n mod 2 = 1: a(n) = (1/147456)*n^10 + (23/73728)*n^9 + (941/147456)*n^8 + (1409/18432)*n^7 + (43777/73728)*n^6 + (115189/36864)*n^5 + (831857/73728)*n^4 + (169595/6144)*n^3 + (717525/16384)*n^2 + (333375/8192)*n + (275625/16384).

a(n+1)=A202095(n). - R. J. Mathar, Dec 04 2014

EXAMPLE

Some solutions for n=6

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

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

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

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

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

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

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

CROSSREFS

Sequence in context: A204391 A233903 A233897 * A033696 A233653 A233646

Adjacent sequences:  A250425 A250426 A250427 * A250429 A250430 A250431

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 22 2014

STATUS

approved

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Last modified September 27 02:43 EDT 2021. Contains 347673 sequences. (Running on oeis4.)