A225978 Number of nX4 binary arrays whose sum with another nX4 binary array containing no more than two 1s has rows and columns in lexicographically nondecreasing order

15, 138, 1178, 9113, 61808, 361361, 1825607, 8065278, 31631401, 111785599, 360788468, 1075829429, 2993017696, 7832960008, 19417916324, 45865067963, 103734768130, 225619306783, 473616394498, 962612525277, 1899542726132

Offset

1,1

Comments

Column 4 of A225982

Links

R. H. Hardin, Table of n, a(n) for n = 1..76

Formula

Empirical: a(n) = (23/14820309504000)*n^17 + (397/2615348736000)*n^16 + (1429/217945728000)*n^15 + (21083/130767436800)*n^14 + (156407/62270208000)*n^13 + (375707/14370048000)*n^12 + (3136061/16765056000)*n^11 + (21563/22861440)*n^10 + (26402329/6096384000)*n^9 + (423919927/18289152000)*n^8 + (68634593/598752000)*n^7 + (144700261/1437004800)*n^6 + (19312991563/12108096000)*n^5 - (22496273857/4540536000)*n^4 + (97668459683/3027024000)*n^3 - (41460631/700700)*n^2 + (20134601/291720)*n - 23 for n>2

Example

Some solutions for n=3
..0..0..0..1....0..0..1..1....0..0..1..1....0..0..0..1....0..0..0..1
..0..1..0..1....0..0..0..0....1..0..0..0....1..1..1..0....0..0..0..1
..1..0..1..1....1..0..0..1....0..0..0..1....0..1..0..0....1..1..0..1

Crossrefs

Sequence in context: A126536 A299033 A030056 * A175707 A123955 A027802

Adjacent sequences: A225975 A225976 A225977 * A225979 A225980 A225981

Keyword

nonn

Author

R. H. Hardin May 22 2013

Status

approved