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 A092399 Row 5 of array in A288580. 9
 1, 1, 2, -6, -4, -25, -24, -42, 336, 216, 2500, 2376, 4032, -52416, -33264, -562500, -532224, -891072, 16039296, 10112256, 225000000, 212357376, 352864512, -8115883776, -5096577024, -140625000000, -132511002624, -219128861952, 6135608134656, 3842819076096, 126562500000000 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 REFERENCES F. Smarandache, Back and Forth Factorials, Arizona State Univ., Special Collections, 1972. LINKS J. Dezert, ed., Smarandacheials (1), Mathematics Magazine for Grades 1-12, No. 4, 2004. J. Dezert, ed., Smarandacheials (2), Mathematics Magazine for Grades 1-12, No. 4, 2004. FORMULA a(n) = !n!_5 = Prod_{i=0, 1, 2, ... .}_{0<|n-5i|<=n}(n-5i) = n(n-5)(n-10).... EXAMPLE !11!_5 = 11(11-5)(11-10)(11-15)(11-20) = 11(6)(1)(-4)(-9) = 2376. MAPLE T:=proc(n, k) local i, p; p:=1; for i from 0 to floor(2*n/k) do if n-k*i <> 0 then p:=p*(n-k*i) fi; od: p; end; r:=k->[seq(T(n, k), n=0..60)]; r(5); # N. J. A. Sloane, Jul 03 2017 CROSSREFS Cf. A288580. Sequence in context: A218973 A106831 A038212 * A039656 A263326 A226532 Adjacent sequences:  A092396 A092397 A092398 * A092400 A092401 A092402 KEYWORD sign AUTHOR J. Dezert (Jean.Dezert(AT)onera.fr), Mar 21 2004 EXTENSIONS Entry revised by N. J. A. Sloane, Jul 03 2017 STATUS approved

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Last modified April 23 06:08 EDT 2019. Contains 322381 sequences. (Running on oeis4.)