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%I #26 Sep 08 2022 08:44:39
%S 1,1,10,910,746200,5507702200,365876657146000,218747042884536166000,
%T 1177042838234827583459440000,57001313848230245122464621625840000,
%U 24843911488189148287648216529610193612000000,97453533413342456299179976631323547842824103012000000
%N q-factorial numbers for q=9.
%H Vincenzo Librandi, <a href="/A015008/b015008.txt">Table of n, a(n) for n = 0..40</a>
%H <a href="/index/Fa#factorial">Index entries for sequences related to factorial numbers</a>
%F a(n) = Product_{k=1..n} (9^k - 1) / (9 - 1).
%F a(0) = 1, a(n) = (9^n - 1)*a(n-1)/8. - _Vincenzo Librandi_, Oct 26 2012
%t RecurrenceTable[{a[1]==1, a[n]==((9^n - 1) * a[n-1])/8}, a, {n, 15}] (* _Vincenzo Librandi_, Oct 26 2012 *)
%t Table[QFactorial[n, 9], {n, 15}] (* _Bruno Berselli_, Aug 14 2013 *)
%o (Magma) [n le 1 select 1 else (9^n - 1)*Self(n-1)/8: n in [1..15]]; // _Vincenzo Librandi_, Oct 26 2012
%Y Cf. A015001, A015002, A015004, A015005, A015006, A015007, A015009, A015011.
%Y Column q=9 of A069777.
%K nonn,easy
%O 0,3
%A _Olivier Gérard_
%E a(0)=1 prepended by _Alois P. Heinz_, Sep 08 2021