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A223673 Number of 6Xn 0..1 arrays with rows, diagonals and antidiagonals unimodal 1
64, 4096, 61996, 321163, 1023339, 2715255, 6789502, 16634224, 40086061, 94218637, 214377471, 470774847, 998649425, 2051656863, 4092563126, 7942987666, 15025087905, 27743027247, 50072239147, 88451496245, 153108327757 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 6 of A223669

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..129

FORMULA

Empirical: a(n) = (271/5443200)*n^12 - (5527/1995840)*n^11 + (284203/2721600)*n^10 - (97799/51840)*n^9 - (4335667/259200)*n^8 + (68712079/30240)*n^7 - (50002254419/680400)*n^6 + (495395854627/362880)*n^5 - (42767475646507/2721600)*n^4 + (1367715597167/12960)*n^3 - (3261545344751/10800)*n^2 - (3687840940699/6930)*n + 4224261488 for n>20

EXAMPLE

Some solutions for n=4

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

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

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

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

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

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

CROSSREFS

Sequence in context: A017571 A016746 A189268 * A189621 A189693 A188744

Adjacent sequences:  A223670 A223671 A223672 * A223674 A223675 A223676

KEYWORD

nonn

AUTHOR

R. H. Hardin Mar 25 2013

STATUS

approved

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Last modified July 4 19:41 EDT 2022. Contains 355084 sequences. (Running on oeis4.)