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A227057 Number of nX3 -2..2 arrays of 2X2 subblock diagonal sums minus antidiagonal sums for some (n+1)X4 binary array with rows and columns of the latter in lexicographically nondecreasing order 1
20, 124, 643, 2934, 11810, 42295, 136553, 402898, 1099681, 2805516, 6748051, 15412421, 33626114, 70430760, 142218700, 277853319, 526833214, 972034792, 1749218167, 3076360168, 5297051430, 8943742393, 14828643583, 24172697248 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A227060

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..39

FORMULA

Empirical: a(n) = (1/1307674368000)*n^15 + (1/10897286400)*n^14 + (47/9340531200)*n^13 + (79/479001600)*n^12 + (25931/7185024000)*n^11 + (347/6220800)*n^10 + (143197/228614400)*n^9 + (1567309/304819200)*n^8 + (5780059/186624000)*n^7 + (244579/1741824)*n^6 + (370033369/718502400)*n^5 + (25976963/17107200)*n^4 + (4033604297/1135134000)*n^3 + (958946909/151351200)*n^2 + (55255/8008)*n + 1

EXAMPLE

Some solutions for n=3

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

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

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

CROSSREFS

Sequence in context: A004634 A222859 A263545 * A263543 A249709 A250648

Adjacent sequences:  A227054 A227055 A227056 * A227058 A227059 A227060

KEYWORD

nonn

AUTHOR

R. H. Hardin Jun 30 2013

STATUS

approved

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Last modified October 31 08:46 EDT 2020. Contains 338101 sequences. (Running on oeis4.)