A015025 - OEIS

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A015025

q-factorial numbers for q=-10.

1, -9, -819, 744471, 6767985861, -615270826637649, -559337171058846967059, 5084883322413411422459366631, 462262120681663158624798004859942421, -420238291486760860506028808179511473194550689

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,2

LINKS

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

FORMULA

Prod_{k=1}^{n} (q^k - 1) / (q - 1).

a(1) = 1, a(n) = ((-10)^n - 1)*a(n-1)/(-11). - Vincenzo Librandi, Oct 26 2012

MATHEMATICA

RecurrenceTable[{a[1]==1, a[n]==(((-10)^n - 1) * a[n-1])/(-11)}, a, {n, 15}] (* Vincenzo Librandi, Oct 26 2012 *)

PROG

(Magma) [n le 1 select 1 else ((-10)^n - 1)*Self(n-1)/(-11): n in [1..13]]; // Vincenzo Librandi, Oct 26 2012