This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A015007 #28 Jul 06 2025 10:12:23
%S A015007 1,1,9,657,384345,1799118945,67375205371305,20185139902805378865,
%T A015007 48378633136349277767794425,927610024989668734297857360967425,
%U A015007 142287668466497494704440569679875994730825,174605966461872393482359052970987514818406771638225
%N A015007 q-factorial numbers for q=8.
%H A015007 Vincenzo Librandi, <a href="/A015007/b015007.txt">Table of n, a(n) for n = 0..40</a>
%H A015007 <a href="/index/Fa#factorial">Index entries for sequences related to factorial numbers</a>.
%F A015007 a(n) = Product_{k=1..n} ((q^k - 1) / (q - 1)), with q=8.
%F A015007 a(0) = 1, a(n) = (8^n-1)*a(n-1)/7. - _Vincenzo Librandi_, Oct 26 2012
%F A015007 From _Amiram Eldar_, Jul 05 2025: (Start)
%F A015007 a(n) = Product_{k=1..n} A023001(k).
%F A015007 a(n) ~ c * 8^(n*(n+1)/2)/7^n, where c = A132036. (End)
%t A015007 RecurrenceTable[{a[1]==1, a[n]==((8^n - 1) * a[n-1])/7}, a, {n, 15}] (* _Vincenzo Librandi_, Oct 26 2012 *)
%t A015007 Table[QFactorial[n, 8], {n, 15}] (* _Bruno Berselli_, Aug 14 2013 *)
%o A015007 (Magma) [n le 1 select 1 else (8^n-1)*Self(n-1)/7: n in [1..15]]; // _Vincenzo Librandi_, Oct 26 2012
%Y A015007 Cf. A015001, A015002, A015004, A015005, A015006, A015008, A015009, A015011.
%Y A015007 Column q=8 of A069777.
%Y A015007 Cf. A023001, A132036.
%K A015007 nonn,easy
%O A015007 0,3
%A A015007 _Olivier Gérard_
%E A015007 a(0)=1 prepended by _Alois P. Heinz_, Sep 08 2021