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A325498
Difference sequence of A036668.
3
3, 1, 1, 1, 2, 2, 2, 3, 1, 2, 1, 3, 1, 1, 3, 1, 1, 1, 4, 1, 1, 4, 1, 1, 1, 1, 2, 2, 3, 1, 1, 1, 4, 2, 2, 1, 1, 1, 1, 1, 3, 2, 3, 1, 1, 1, 1, 1, 2, 2, 4, 2, 1, 3, 1, 1, 2, 1, 1, 1, 1, 4, 2, 3, 1, 1, 1, 1, 1, 2, 1, 1, 3, 1, 2, 4, 2, 4, 1, 1, 1, 3, 1, 1, 3, 1
OFFSET
1,1
COMMENTS
See A325417 for a guide to related sequences.
Conjecture: every term is in {1,2,3,4}.
LINKS
FORMULA
Asymptotic mean: lim_{n->oo} (1/n) * Sum_{k=1..n} a(k) = 12/7. - Amiram Eldar, Nov 26 2020
EXAMPLE
A036668 is given by A(n) = least number not 2*A(m) or 3*A(m) for any m < n, so that A = (1,4,5,6,7,9,11,...), with differences (3,1,1,1,2,2,...).
MATHEMATICA
a = {1}; Do[AppendTo[a, NestWhile[# + 1 &, Last[a] + 1,
Apply[Or, Map[MemberQ[a, #] &, Select[Flatten[{#/3, #/2}],
IntegerQ]]] &]], {2000}]; a ; (* A036668 *)
c = Complement[Range[Last[a]], a] ; (* A325424 *)
Differences[a] (* A325498 *)
Differences[c] (* A325499 *)
(* Peter J. C. Moses, Apr 23 2019 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, May 05 2019
STATUS
approved