%I #9 Jul 06 2024 12:14:40
%S 1,2,5,15,52,203,877,4140,21147,115975,678570,4213597,27644437,
%T 190899322,1382958545,10480142147,82864869803,682076806005,
%U 5832742192288,51724157478221,474869780161021,4506714279517080,44151953491540255
%N Number of arrays of n 0..15 integers with new values introduced in order 0..15 but otherwise unconstrained.
%C Column 15 of A203647.
%H R. H. Hardin, <a href="/A203646/b203646.txt">Table of n, a(n) for n = 1..210</a>
%H <a href="/index/Rec#order_15">Index entries for linear recurrences with constant coefficients</a>, signature (121, -6685, 223405, -5042947, 81308227, -965408015, 8576039615, -57312583328, 287212533608, -1066335473840, 2866534951280, -5367984964224, 6557974412544, -4622628648960, 1394852659200).
%F Empirical: a(n) = 121*a(n-1) -6685*a(n-2) +223405*a(n-3) -5042947*a(n-4) +81308227*a(n-5) -965408015*a(n-6) +8576039615*a(n-7) -57312583328*a(n-8) +287212533608*a(n-9) -1066335473840*a(n-10) +2866534951280*a(n-11) -5367984964224*a(n-12) +6557974412544*a(n-13) -4622628648960*a(n-14) +1394852659200*a(n-15).
%F Empirical formula confirmed by extension of first ten columns, see A203641. - _Ray Chandler_, Jul 06 2024
%Y Cf. A203641.
%K nonn
%O 1,2
%A _R. H. Hardin_, Jan 04 2012