A223996 Number of nX5 0..2 arrays with antidiagonals unimodal and rows and diagonals nondecreasing.
21, 281, 2403, 17929, 132119, 984595, 7400832, 55978489, 425257387, 3240026429, 24732295031, 189012200658, 1445524081573, 11059812977060, 84641528773971, 647871404690124, 4959498660501284, 37967742496830194, 290676685330836460
Offset: 1
Keywords
Examples
Some solutions for n=3 ..0..0..0..0..0....0..1..1..1..1....0..0..0..0..0....1..1..1..1..2 ..0..0..0..2..2....1..1..1..1..1....0..1..1..1..2....0..2..2..2..2 ..1..1..1..1..2....0..1..1..2..2....0..2..2..2..2....2..2..2..2..2
Links
- R. H. Hardin, Table of n, a(n) for n = 1..210
Formula
Empirical: a(n) = 21*a(n-1) -155*a(n-2) +405*a(n-3) +365*a(n-4) -2996*a(n-5) -664*a(n-6) +18276*a(n-7) -22433*a(n-8) -2304*a(n-9) -9369*a(n-10) -7644*a(n-11) +222262*a(n-12) +167540*a(n-13) -1508772*a(n-14) +2046821*a(n-15) -1097976*a(n-16) +4265706*a(n-17) -2582500*a(n-18) -941886*a(n-19) -2423080*a(n-20) +19902336*a(n-21) +2548764*a(n-22) +9439760*a(n-23) +1688032*a(n-24) +1035840*a(n-25) -957120*a(n-26) +1996416*a(n-27) -115200*a(n-28) for n>31
Comments