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A015005
q-factorial numbers for q=6.
10
1, 1, 7, 301, 77959, 121226245, 1131162092095, 63330372050122765, 21274128570193389587095, 42878835824239014254983869205, 518543838148941095553869851505328175, 37625235473766496167083515195884075739704925, 16380389585902052954270520869620904155598347770499975
OFFSET
0,3
FORMULA
a(n) = Product_{k=1..n} (6^k-1)/(6-1).
a(0) = 1, a(n) = (6^n-1)*a(n-1)/5. - Vincenzo Librandi, Oct 25 2012
MATHEMATICA
RecurrenceTable[{a[1]==1, a[n]==((6^n - 1) * a[n-1])/5}, a, {n, 15}] (* Vincenzo Librandi, Oct 25 2012 *)
Table[QFactorial[n, 6], {n, 15}] (* Bruno Berselli, Aug 14 2013 *)
PROG
(Magma) [n le 1 select 1 else (6^n-1)*Self(n-1)/5: n in [1..15]]; // Vincenzo Librandi, Oct 25 2012
CROSSREFS
KEYWORD
nonn,easy
EXTENSIONS
a(0)=1 prepended by Alois P. Heinz, Sep 08 2021
STATUS
approved