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 A092972 #11 Jul 03 2017 16:13:48
%S A092972 1,1,2,3,-12,-10,-6,-49,-48,-90,-120,1320,1080,624,9604,9360,17280,
%T A092972 22440,-403920,-328320,-187200,-4235364,-4118400,-7551360,-9694080,
%U A092972 242352000,196335360,111196800,3320525376,3224707200,5890060800,7512912000,-240413184000,-194372006400,-109640044800
%N A092972 Row 7 of array in A288580.
%D A092972 F. Smarandache, Back and Forth Factorials, Arizona State Univ., Special Collections, 1972.
%H A092972 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 A092972 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 A092972 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=7.
%p A092972 T:=proc(n,k) local i,p;
%p A092972 p:=1;
%p A092972 for i from 0 to floor(2*n/k) do
%p A092972 if n-k*i <> 0 then p:=p*(n-k*i) fi; od:
%p A092972 p;
%p A092972 end;
%p A092972 r:=k->[seq(T(n,k), n=0..60)]; r(7); # _N. J. A. Sloane_, Jul 03 2017
%o A092972 (PARI) a(n,k)=prod(j=0,(2*n)\k,if(n-k*j==0,1,n-k*j))
%Y A092972 Cf. A288580, A092396, A092397, A092398, A092399, A092971, A092973, A092974.
%K A092972 sign
%O A092972 0,3
%A A092972 Paul D. Hanna, M.L. Perez and _Amarnath Murthy_, Mar 27 2004
%E A092972 Entry revised by _N. J. A. Sloane_, Jul 03 2017