A283891 Relative of Hofstadter Q-sequence.

28, 10001, 10002, 10003, 10004, 10005, 10006, 10007, 35, 10008, 10009, 10010, 10011, 10012, 10013, 10014, 42, 10015, 10016, 10017, 10018, 10019, 10020, 10021, 49, 10022, 10023, 10024, 10025, 10026, 10027, 10028, 56, 10029, 10030, 10031, 10032, 10033, 10034, 10035, 63

Offset

1,1

Comments

This sequence is defined by a(n) = max(0, n+10000) 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.

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 10000 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

A283891:=proc(n) option remember: if n <= 0 then max(0, n+10000): else A283891(n-A283891(n-1)) + A283891(n-A283891(n-2)) + A283891(n-A283891(n-3)) + A283891(n-A283891(n-4)) + A283891(n-A283891(n-5)) + A283891(n-A283891(n-6)) + A283891(n-A283891(n-7)): fi: end:

Crossrefs

Cf. A005185, A283889, A283890, A283892.

Sequence in context: A099058 A281128 A222018 * A283892 A281652 A221691

Adjacent sequences: A283888 A283889 A283890 * A283892 A283893 A283894

Keyword

nonn,look

Author

Nathan Fox, Mar 19 2017

Status

approved