Number of 9Xn -1,1 arrays such that the sum over i=1..9,j=1..n of i*x(i,j) is zero, the sum of x(i,j) is zero, and rows are nondecreasing (number of ways to distribute n-across galley oarsmen left-right at 9 fore-aft positions so that there are no turning moments on the ship).
A225349
Number of 9Xn -1,1 arrays such that the sum over i=1..9,j=1..n of i*x(i,j) is zero, the sum of x(i,j) is zero, and rows are nondecreasing (number of ways to distribute n-across galley oarsmen left-right at 9 fore-aft positions so that there are no turning moments on the ship).
Terms
- a(0) =0a(1) =181a(2) =0a(3) =6095a(4) =0a(5) =63121a(6) =0a(7) =364051a(8) =0a(9) =1478059a(10) =0a(11) =4749875a(12) =0a(13) =12917383a(14) =0a(15) =30996867a(16) =0a(17) =67483509a(18) =0a(19) =135917019a(20) =0a(21) =256859575a(22) =0a(23) =460336079a(24) =0a(25) =788783775a(26) =0a(27) =1300561813a(28) =0a(29) =2074066679
External references
- oeis: A225349