A278672 Number of nX4 0..1 arrays with rows in nondecreasing lexicographic order and columns in nonincreasing lexicographic order, but with exactly one mistake.

10, 99, 579, 2650, 10584, 38848, 134265, 441349, 1384443, 4148373, 11882640, 32576006, 85619948, 216195769, 525654868, 1233512143, 2800037121, 6161774705, 13172137674, 27405600826, 55592487870, 110125213825, 213350721015

Offset

1,1

Comments

Column 4 of A278676.

Links

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

Formula

Empirical: a(n) = (1/2432902008176640000)*n^20 + (1/16219346721177600)*n^19 + (113/25609494822912000)*n^18 + (19/94849980825600)*n^17 + (2719/418455797760000)*n^16 + (6689/41845579776000)*n^15 + (2324129/753220435968000)*n^14 + (1200247/25107347865600)*n^13 + (351438179/579400335360000)*n^12 + (1259149/195084288000)*n^11 + (254340707/4291854336000)*n^10 + (620067937/1287556300800)*n^9 + (236029006781/67251824640000)*n^8 + (715300432229/31384184832000)*n^7 + (12122971872241/94152554496000)*n^6 + (39838863931/69742632960)*n^5 + (192914714452637/111152321280000)*n^4 + (1979357687401/617512896000)*n^3 + (1837396540403/586637251200)*n^2 + (3628307/3023280)*n

Example

Some solutions for n=4
..0..0..0..0. .0..0..0..0. .1..0..1..0. .0..0..0..0. .1..1..0..0
..1..1..1..0. .0..0..1..1. .1..0..1..0. .1..1..0..0. .0..0..1..1
..0..0..0..0. .1..0..0..0. .1..0..1..0. .1..0..1..1. .1..0..1..1
..1..1..1..1. .1..0..1..1. .1..1..1..0. .1..1..1..0. .1..1..1..0

Crossrefs

Cf. A278676.

Sequence in context: A361137 A135927 A299952 * A129542 A359482 A224752

Adjacent sequences: A278669 A278670 A278671 * A278673 A278674 A278675

Keyword

nonn

Author

R. H. Hardin, Nov 25 2016

Status

approved