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A226868 Number of nX4 (-1,0,1) arrays of determinants of 2X2 subblocks of some (n+1)X5 binary array with rows and columns of the latter in lexicographically nondecreasing order 1
11, 91, 792, 6195, 41222, 235528, 1179663, 5279390, 21450391, 80163310, 278497578, 907289100, 2791617118, 8160858953, 22780131186, 60975863607, 157078679556, 390656580964, 940538345174, 2197356106902, 4992114741415, 11049541664919 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 4 of A226870

LINKS

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

FORMULA

Empirical: a(n) = (1/39895087560007680000)*n^23 - (1/1156379349565440000)*n^22 + (31/236532139683840000)*n^21 - (283/90107481784320000)*n^20 + (9067/45053740892160000)*n^19 - (38231/14227497123840000)*n^18 + (514669/5532915548160000)*n^17 + (94049/976396861440000)*n^16 - (1341139/732297646080000)*n^15 + (551917/1107025920000)*n^14 - (3294587311/767168962560000)*n^13 + (32197879519/708155965440000)*n^12 + (449013326383/976396861440000)*n^11 - (17775513984467/1952793722880000)*n^10 + (307489530723593/2929190584320000)*n^9 - (18254938832597/34871316480000)*n^8 + (218159407677791/296406190080000)*n^7 + (10418027129737729/889218570240000)*n^6 - (1942722234280615327/19711011640320000)*n^5 + (573780866912018197/1231938227520000)*n^4 - (483951429128288267/301140455616000)*n^3 + (4624723720846583/1075501627200)*n^2 - (2316066603161/297457160)*n + 6853 for n>5

EXAMPLE

Some solutions for n=4

..0.-1..1..0....0..0..0.-1....0.-1..0..1....0..0..0.-1....0..0..0.-1

..0..0..0..0....0..0.-1..0...-1..1..0.-1....0..0.-1..1....0..0..0..0

..0..1.-1..0...-1..0..1..0....1.-1..1..0...-1..0..1.-1...-1..0..1..0

.-1..0..0..1....0..0.-1..1....0..0..0..1....0..0.-1..1....0..0.-1..0

CROSSREFS

Sequence in context: A125374 A245599 A126532 * A199678 A201549 A117611

Adjacent sequences:  A226865 A226866 A226867 * A226869 A226870 A226871

KEYWORD

nonn

AUTHOR

R. H. Hardin Jun 20 2013

STATUS

approved

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Last modified May 24 06:53 EDT 2019. Contains 323529 sequences. (Running on oeis4.)