A203644 Number of arrays of n 0..13 integers with new values introduced in order 0..13 but otherwise unconstrained.
1, 2, 5, 15, 52, 203, 877, 4140, 21147, 115975, 678570, 4213597, 27644437, 190899322, 1382958544, 10480142026, 82864861847, 682076428809, 5832727748374, 51723682798067, 474855882753977, 4506342616999876, 44142711725983660
Offset: 1
Keywords
Links
- R. H. Hardin, Table of n, a(n) for n = 1..210
- Index entries for linear recurrences with constant coefficients, signature (92, -3809, 93808, -1530243, 17419116, -141963107, 835933384, -3542188936, 10614910592, -21727767984, 28528276608, -21289201920, 6706022400).
Formula
Empirical: a(n) = 92*a(n-1) -3809*a(n-2) +93808*a(n-3) -1530243*a(n-4) +17419116*a(n-5) -141963107*a(n-6) +835933384*a(n-7) -3542188936*a(n-8) +10614910592*a(n-9) -21727767984*a(n-10) +28528276608*a(n-11) -21289201920*a(n-12) +6706022400*a(n-13).
Empirical formula confirmed by extension of first ten columns, see A203641. - Ray Chandler, Jul 06 2024