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A015008 q-factorial numbers for q=9. 2
1, 10, 910, 746200, 5507702200, 365876657146000, 218747042884536166000, 1177042838234827583459440000, 57001313848230245122464621625840000, 24843911488189148287648216529610193612000000 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..40

Index entries for sequences related to factorial numbers

FORMULA

a(n) = product_{k=1..n} (9^k - 1) / (9 - 1).

a(1) = 1, a(n) = (9^n - 1)*a(n-1)/8. - Vincenzo Librandi, Oct 26 2012

MATHEMATICA

RecurrenceTable[{a[1]==1, a[n]==((9^n - 1) * a[n-1])/8}, a, {n, 15}] (* Vincenzo Librandi, Oct 26 2012 *)

Table[QFactorial[n, 9], {n, 15}] (* Bruno Berselli, Aug 14 2013 *)

PROG

(MAGMA) [n le 1 select 1 else (9^n - 1)*Self(n-1)/8: n in [1..15]]; // Vincenzo Librandi, Oct 26 2012

CROSSREFS

Sequence in context: A233125 A297471 A024137 * A194791 A292669 A159869

Adjacent sequences:  A015005 A015006 A015007 * A015009 A015010 A015011

KEYWORD

nonn,easy

AUTHOR

Olivier Gérard

STATUS

approved

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Last modified October 1 08:39 EDT 2020. Contains 337442 sequences. (Running on oeis4.)