A227057 - OEIS

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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

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