A263817 Number of (1+1)X(n+1) arrays of permutations of 0..n*2+1 with each element having index change (+-,+-) 0,0 0,1 0,2 or 1,0.
9, 82, 572, 3682, 25001, 170946, 1157993, 7844192, 53217648, 360982800, 2448043433, 16602594594, 112601971449, 763678525370, 5179331223772, 35126741117978, 238233127708969, 1615720591473218, 10957976653235217
Offset: 1
Keywords
Examples
Some solutions for n=4 ..2..1..0..3..9....0..2..3..1..4....2..0..7..1..4....0..2..4..1..9 ..5..6..8..7..4....6..8..5..9..7....5..6..9..3..8....5..7..6..3..8
Links
- R. H. Hardin, Table of n, a(n) for n = 1..210
Crossrefs
Cf. A263816
Formula
Empirical: a(n) = 8*a(n-1) -7*a(n-2) +6*a(n-3) -62*a(n-4) -316*a(n-5) +338*a(n-6) +756*a(n-7) +310*a(n-8) +856*a(n-9) -2386*a(n-10) -3818*a(n-11) +1730*a(n-12) +1676*a(n-13) +990*a(n-14) +2322*a(n-15) -1106*a(n-16) -924*a(n-17) -42*a(n-18) -452*a(n-19) +210*a(n-20) +112*a(n-21) -30*a(n-22) +34*a(n-23) -9*a(n-24) -4*a(n-25) +a(n-26)
Comments