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 A121459 Let f(n) = A004001(n)^2 - A005185(n)^2. Then a(n) = f(abs(f(n-1))) + f(abs(n - f(n-1))). 1
 0, -3, -14, -18, -7, -9, -47, -51, 0, -15, -15, -48, -17, -36, 57, -151, 0, -63, 0, -11, 0, 25, 26, 368, 29, -5, -96, -33, 0, -144, 2275, -466, -180, 433, 472, 0, -43, 316, 0, 0, 47, -302, 49, 152, 1122, 945, 1273, 10170, 589, 1310, 121, 54, 3117, 0, 177, 2141, -1280, -5, 310, 0 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS G. C. Greubel, Table of n, a(n) for n = 1..350 MATHEMATICA HConway[n_]:= HConway[n]= If[n<3, 1, HConway[HConway[n-1]] + HConway[n-HConway[n -1]]]; Hofstadter[n_]:= Hofstadter[n]= If[n<3, 1, Hofstadter[n -Hofstadter[n-1]] + Hofstadter[n -Hofstadter[n-2]]]; f[n_]:= f[n]= HConway[n]^2 - Hofstadter[n]^2; Table[f[Abs[f[n-1]]] + f[Abs[n -f[n-1]]], {n, 60}] (* corrected by G. C. Greubel, Feb 12 2020 *) CROSSREFS Cf. A004001, A005185. Sequence in context: A032920 A134767 A022125 * A121226 A063633 A108933 Adjacent sequences:  A121456 A121457 A121458 * A121460 A121461 A121462 KEYWORD sign,less AUTHOR Roger L. Bagula, Sep 06 2006 EXTENSIONS Edited by N. J. A. Sloane, Oct 01 2006 Terms a(31) and beyond corrected by G. C. Greubel, Feb 12 2020 STATUS approved

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Last modified April 13 01:36 EDT 2021. Contains 342934 sequences. (Running on oeis4.)