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 A092974 #8 Jul 03 2017 16:12:05
%S A092974 1,1,2,3,4,-20,-18,-14,-8,-81,-80,-154,-216,-260,3640,3240,2464,1360,
%T A092974 26244,25840,49280,68040,80080,-1841840,-1632960,-1232000,-671840,
%U A092974 -19131876,-18811520,-35728000,-48988800,-57097040,1827105280,1616630400,1214752000,658403200,24794911296,24360918400
%N A092974 Row 9 of array in A288580.
%D A092974 F. Smarandache, Back and Forth Factorials, Arizona State Univ., Special Collections, 1972.
%H A092974 J. Dezert, ed., <a href="http://www.mathematicsmagazine.com/corresp/J_Dezert/JDezert.htm">Smarandacheials (1)</a>, Mathematics Magazine for Grades 1-12, No. 4, 2004.
%H A092974 J. Dezert, ed., <a href="http://www.mathematicsmagazine.com/corresp/J_Dezert/JDezert2.htm">Smarandacheials (2)</a>, Mathematics Magazine for Grades 1-12, No. 4, 2004.
%F A092974 a(n, k) = !n!_k = Prod_{i=0, 1, 2, .., floor(2n/k)}_{0<|n-i*k|<=n} (n-i*k) = n(n-k)(n-2k)(n-3k)... . k=9.
%p A092974 T:=proc(n,k) local i,p;
%p A092974 p:=1;
%p A092974 for i from 0 to floor(2*n/k) do
%p A092974 if n-k*i <> 0 then p:=p*(n-k*i) fi; od:
%p A092974 p;
%p A092974 end;
%p A092974 r:=k->[seq(T(n,k), n=0..60)]; r(9); # _N. J. A. Sloane_, Jul 03 2017
%o A092974 (PARI) a(n,k)=prod(j=0,(2*n)\k,if(n-k*j==0,1,n-k*j))
%Y A092974 Cf. A288580, A092396, A092397, A092398, A092399, A092971, A092972, A092973.
%K A092974 sign
%O A092974 0,3
%A A092974 Paul D. Hanna, M.L. Perez and _Amarnath Murthy_, Mar 27 2004