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 A212051 Number of (w,x,y,z) with all terms in {1,...,n} and 3w*x=5*y*z. 2
 0, 0, 0, 0, 0, 16, 28, 32, 40, 52, 112, 120, 164, 172, 192, 280, 310, 322, 398, 410, 580, 644, 680, 696, 816, 1004, 1048, 1138, 1218, 1238, 1592, 1616, 1702, 1798, 1854, 2138, 2394, 2422, 2486, 2598, 3068, 3100, 3368, 3400, 3536, 3976, 4056 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,6 COMMENTS Each term is divisible by 2. See A211795 for a guide to related sequences. LINKS MATHEMATICA t = Compile[{{n, _Integer}}, Module[{s = 0}, (Do[If[3 w*x == 5 y*z, s = s + 1], {w, 1, #}, {x, 1, #}, {y, 1, #}, {z, 1, #}] &[n]; s)]]; Map[t[#] &, Range[0, 50]] (* A212051 *) %/2 (* integers *) (* Peter J. C. Moses, Apr 13 2012 *) CROSSREFS Cf. A211795. Sequence in context: A101857 A350302 A184039 * A166595 A280989 A337663 Adjacent sequences: A212048 A212049 A212050 * A212052 A212053 A212054 KEYWORD nonn AUTHOR Clark Kimberling, Apr 29 2012 STATUS approved

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Last modified March 29 06:08 EDT 2023. Contains 361596 sequences. (Running on oeis4.)