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A253745 Number of (n+1)X(4+1) 0..2 arrays with every 2X2 subblock ne-sw antidiagonal difference nondecreasing horizontally and nw+se diagonal sum nondecreasing vertically 1
7803, 29737, 247252, 1143174, 5195288, 17656505, 54890203, 150904540, 390365827, 928677156, 2090553259, 4473135405, 9220179921, 18291567088, 35191833486, 65909750009, 120749865702, 216723296865, 382241803433, 663962769116 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 4 of A253749

LINKS

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

FORMULA

Empirical: a(n) = 7*a(n-1) -21*a(n-2) +36*a(n-3) -34*a(n-4) -11*a(n-5) +107*a(n-6) -199*a(n-7) +198*a(n-8) -46*a(n-9) -232*a(n-10) +461*a(n-11) -440*a(n-12) +141*a(n-13) +295*a(n-14) -581*a(n-15) +490*a(n-16) -120*a(n-17) -270*a(n-18) +435*a(n-19) -274*a(n-20) -17*a(n-21) +201*a(n-22) -201*a(n-23) +54*a(n-24) +86*a(n-25) -112*a(n-26) +59*a(n-27) +12*a(n-28) -49*a(n-29) +37*a(n-30) -11*a(n-31) -5*a(n-32) +9*a(n-33) -5*a(n-34) +a(n-35) for n>47

EXAMPLE

Some solutions for n=2

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

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

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

CROSSREFS

Sequence in context: A234032 A290339 A234460 * A253752 A252317 A250026

Adjacent sequences:  A253742 A253743 A253744 * A253746 A253747 A253748

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 11 2015

STATUS

approved

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Last modified May 11 15:53 EDT 2021. Contains 343792 sequences. (Running on oeis4.)