A223967 Number of 7Xn 0..3 arrays with antidiagonals unimodal and rows and diagonals nondecreasing.
16384, 3342081, 68892600, 559416917, 2772658693, 10269723035, 31770135236, 87719331172, 225263690895, 552379261275, 1315281342539, 3072993757981, 7087865594659, 16189704679316, 36662195998974, 82296709582927
Offset: 1
Keywords
Examples
Some solutions for n=3 ..0..0..0....0..0..0....0..0..0....0..0..0....0..0..0....0..0..0....0..0..0 ..0..0..0....0..0..0....0..0..0....0..0..0....0..0..0....0..0..0....0..0..0 ..0..0..0....0..0..0....0..0..1....0..0..0....0..0..3....0..0..1....0..0..0 ..0..0..0....0..0..3....0..2..3....0..0..0....0..1..2....0..0..3....0..0..2 ..0..0..0....0..1..1....0..1..3....1..1..3....0..3..3....0..1..1....1..1..1 ..0..0..2....1..1..3....0..3..3....0..2..2....1..1..3....1..1..2....1..1..1 ..0..1..1....0..1..2....0..2..3....1..2..3....1..1..1....1..2..2....2..3..3
Links
- R. H. Hardin, Table of n, a(n) for n = 1..210
Formula
Empirical: a(n) = (1/36870930432000)*n^21 + (1/1755758592000)*n^20 + (7987/292065067008000)*n^19 + (193003/284549942476800)*n^18 + (17759011/1067062284288000)*n^17 + (1347607/3804143616000)*n^16 + (18694718671/2636271525888000)*n^15 + (3112211369/25107347865600)*n^14 + (20604917909/9782083584000)*n^13 + (70370427983/2145927168000)*n^12 + (1850924201039/3862668902400)*n^11 + (147887455837/23410114560)*n^10 + (3273669680467127/40558023475200)*n^9 + (412868001184691/482833612800)*n^8 + (28540139678997911/3362591232000)*n^7 + (7031336918804501/95103590400)*n^6 + (100407456813399821/290594304000)*n^5 + (203722361032935541/108972864000)*n^4 - (63818340288729017/11557728000)*n^3 - (185169857197901243/1286485200)*n^2 + (456453009190537/5819814)*n + 2553072919 for n>14
Comments