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 A283890 Relative of Hofstadter Q-sequence: a(n) = max(0, n+10001) for n <= 0; a(n) = a(n-a(n-1)) + a(n-a(n-2)) + a(n-a(n-3)) + a(n-a(n-4)) for n > 0. 4
 10, 10002, 10003, 10004, 10005, 14, 10006, 10007, 10008, 10009, 18, 10010, 10011, 10012, 10013, 22, 10014, 10015, 10016, 10017, 26, 10018, 10019, 10020, 10021, 30, 10022, 10023, 10024, 10025, 34, 10026, 10027, 10028, 37, 10030, 10030, 39 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Sequences like this are more naturally considered with the first nonzero term in position 1. But this sequence would then match A000027 for its first 10001 terms. This sequence has some stretches where it is quasilinear, but it appears to be ultimately chaotic. LINKS Nathan Fox, Table of n, a(n) for n = 1..50000 MAPLE A283890:=proc(n) option remember: if n <= 0 then max(0, n+10001): else A283890(n-A283890(n-1)) + A283890(n-A283890(n-2)) + A283890(n-A283890(n-3)) + A283890(n-A283890(n-4)): fi: end: CROSSREFS Cf. A005185, A283889, A283891, A283892. Sequence in context: A076782 A213653 A283889 * A139109 A317959 A119037 Adjacent sequences:  A283887 A283888 A283889 * A283891 A283892 A283893 KEYWORD nonn,look AUTHOR Nathan Fox, Mar 19 2017 STATUS approved

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Last modified December 16 06:18 EST 2019. Contains 330016 sequences. (Running on oeis4.)