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A223678 Number of nX6 0..1 arrays with rows and antidiagonals unimodal 1
22, 484, 7745, 105995, 1363639, 17068664, 210660192, 2577807779, 31402790284, 381690187059, 4633795630120, 56218000664764, 681802614308980, 8267243693472174, 100235088136900011, 1215221703756846658 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 6 of A223680

LINKS

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

FORMULA

Empirical: a(n) = 22*a(n-1) -151*a(n-2) +461*a(n-3) -797*a(n-4) -4885*a(n-5) +28261*a(n-6) +53750*a(n-7) -398208*a(n-8) +360701*a(n-9) +952132*a(n-10) -5152120*a(n-11) +7572284*a(n-12) +6140578*a(n-13) -18089482*a(n-14) -653352*a(n-15) +28175814*a(n-16) +67786763*a(n-17) -392210630*a(n-18) +717516941*a(n-19) -875602031*a(n-20) +904784133*a(n-21) -930560603*a(n-22) +1037859554*a(n-23) -1035189626*a(n-24) +1256680629*a(n-25) -1842818297*a(n-26) +2256596552*a(n-27) -2217424297*a(n-28) +1613743557*a(n-29) -832569368*a(n-30) +412448612*a(n-31) -308789168*a(n-32) +241553248*a(n-33) -122269952*a(n-34) +31245376*a(n-35) -2822400*a(n-36)

EXAMPLE

Some solutions for n=3

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

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

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

CROSSREFS

Sequence in context: A223667 A223826 A223618 * A223784 A223970 A171296

Adjacent sequences:  A223675 A223676 A223677 * A223679 A223680 A223681

KEYWORD

nonn

AUTHOR

R. H. Hardin Mar 25 2013

STATUS

approved

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Last modified December 1 21:20 EST 2021. Contains 349435 sequences. (Running on oeis4.)