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 A127145 Q(3,n), where Q(m,k) is defined in A127080 and A127137, 4
 1, 1, 1, -2, -9, 4, 75, 24, -735, -816, 8505, 17760, -114345, -388800, 1756755, 9233280, -30405375, -242968320, 585810225, 7125511680, -12439852425, -232838323200, 288735522075, 8450546227200, -7273385294175, -339004760371200, 197646339515625, 14945696794828800, -5763367260275625 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,4 REFERENCES V. van der Noort and N. J. A. Sloane, Paper in preparation, 2007. LINKS G. C. Greubel, Table of n, a(n) for n = 0..500 FORMULA See A127080 for e.g.f. MAPLE Q:= proc(n, k) option remember;       if k<2 then 1     elif `mod`(k, 2)=0 then (n-k+1)*Q(n+1, k-1) - (k-1)*Q(n+2, k-2)     else ( (n-k+1)*Q(n+1, k-1) - (k-1)*(n+1)*Q(n+2, k-2) )/n       fi; end; seq( Q(3, n), n=0..30); # G. C. Greubel, Jan 30 2020 MATHEMATICA Q[n_, k_]:= Q[n, k]= If[k<2, 1, If[EvenQ[k], (n-k+1)*Q[n+1, k-1] - (k-1)*Q[n + 2, k-2], ((n-k+1)*Q[n+1, k-1] - (k-1)*(n+1)*Q[n+2, k-2])/n]]; Table[Q[3, k], {k, 0, 30}] (* G. C. Greubel, Jan 30 2020 *) PROG (Sage) @CachedFunction def Q(n, k):     if (k<2): return 1     elif (mod(k, 2)==0): return (n-k+1)*Q(n+1, k-1) - (k-1)*Q(n+2, k-2)     else: return ( (n-k+1)*Q(n+1, k-1) - (k-1)*(n+1)*Q(n+2, k-2) )/n [Q(3, n) for n in (0..30)] # G. C. Greubel, Jan 30 2020 CROSSREFS Cf. A126965. Column 3 of A127080. Cf. A127137, A127138, A127144. Sequence in context: A268249 A268246 A268103 * A210423 A003725 A292952 Adjacent sequences:  A127142 A127143 A127144 * A127146 A127147 A127148 KEYWORD sign AUTHOR N. J. A. Sloane, Mar 24 2007 STATUS approved

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Last modified January 20 00:50 EST 2021. Contains 340300 sequences. (Running on oeis4.)