%I
%S 28,10002,10003,10004,10005,10006,10007,10008,35,10009,10010,10011,
%T 10012,10013,10014,10015,42,10016,10017,10018,10019,10020,10021,10022,
%U 49,10023,10024,10025,10026,10027,10028,10029,56,10030,10031,10032,10033,10034,10035,10036,63
%N Relative of Hofstadter Q-sequence.
%C This sequence is defined by 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)) + a(n-a(n-5)) + a(n-a(n-6)) + a(n-a(n-7)) for n > 0.
%C 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.
%C This sequence has some stretches where it is quasilinear, but it appears to be ultimately chaotic.
%H Nathan Fox, <a href="/A283892/b283892.txt">Table of n, a(n) for n = 1..50000</a>
%p A283892:=proc(n) option remember: if n <= 0 then max(0, n+10001): else A283892(n-A283892(n-1)) + A283892(n-A283892(n-2)) + A283892(n-A283892(n-3)) + A283892(n-A283892(n-4)) + A283892(n-A283892(n-5)) + A283892(n-A283892(n-6)) + A283892(n-A283892(n-7)): fi: end:
%Y Cf. A005185, A283889, A283890, A283891.
%K nonn
%O 1,1
%A _Nathan Fox_, Mar 19 2017
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