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A253746 Number of (n+1)X(5+1) 0..2 arrays with every 2X2 subblock ne-sw antidiagonal difference nondecreasing horizontally and nw+se diagonal sum nondecreasing vertically 1
28107, 70590, 583698, 2351928, 10966149, 36766701, 112645903, 295452432, 734787935, 1658583509, 3510427759, 6967556836, 13254580819, 24069157677, 42106383208, 71123318652, 116864959320, 186850930571, 291778710900 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 5 of A253749

LINKS

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

FORMULA

Empirical: a(n) = 6*a(n-1) -15*a(n-2) +20*a(n-3) -10*a(n-4) -24*a(n-5) +74*a(n-6) -100*a(n-7) +65*a(n-8) +30*a(n-9) -145*a(n-10) +200*a(n-11) -140*a(n-12) +140*a(n-14) -200*a(n-15) +145*a(n-16) -30*a(n-17) -65*a(n-18) +100*a(n-19) -74*a(n-20) +24*a(n-21) +10*a(n-22) -20*a(n-23) +15*a(n-24) -6*a(n-25) +a(n-26) for n>41

Empirical for n mod 4 = 0: a(n) = (3217/1612800)*n^10 + (33679/138240)*n^9 + (1422807/143360)*n^8 + (18404459/322560)*n^7 - (368077919/460800)*n^6 + (418588771/46080)*n^5 - (917187479/40320)*n^4 - (3006869237/17280)*n^3 + (76331484091/50400)*n^2 - (289830581/70)*n + 3817900 for n>15

Empirical for n mod 4 = 1: a(n) = (3217/1612800)*n^10 + (33679/138240)*n^9 + (1422807/143360)*n^8 + (18404459/322560)*n^7 - (368077919/460800)*n^6 + (418588771/46080)*n^5 - (7213283887/322560)*n^4 - (22717166311/138240)*n^3 + (4818663442399/3225600)*n^2 - (55832024207/13440)*n + (16023849991/4096) for n>15

Empirical for n mod 4 = 2: a(n) = (3217/1612800)*n^10 + (33679/138240)*n^9 + (1422807/143360)*n^8 + (18404459/322560)*n^7 - (368077919/460800)*n^6 + (418588771/46080)*n^5 - (1802294623/80640)*n^4 - (349731199/2160)*n^3 + (286627480189/201600)*n^2 - (25624890491/6720)*n + (29304949/8) for n>15

Empirical for n mod 4 = 3: a(n) = (3217/1612800)*n^10 + (33679/138240)*n^9 + (1422807/143360)*n^8 + (18404459/322560)*n^7 - (368077919/460800)*n^6 + (418588771/46080)*n^5 - (7166029267/322560)*n^4 - (21877961311/138240)*n^3 + (4564135470799/3225600)*n^2 - (8542155047/2240)*n + (15090544151/4096) for n>15

EXAMPLE

Some solutions for n=2

..1..0..0..0..2..2....0..0..1..0..1..1....0..0..0..0..1..2....2..1..1..1..1..2

..1..0..0..1..1..1....0..1..0..1..1..2....2..0..0..1..1..2....2..1..1..1..0..0

..1..1..2..2..1..2....2..1..2..2..0..2....0..0..1..1..2..2....2..2..2..1..0..2

CROSSREFS

Sequence in context: A247992 A236093 A116462 * A253753 A203832 A237246

Adjacent sequences:  A253743 A253744 A253745 * A253747 A253748 A253749

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 11 2015

STATUS

approved

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Last modified June 13 11:07 EDT 2021. Contains 344989 sequences. (Running on oeis4.)