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A317359
a(0) = 0, a(1) = 1; for n >= 2, a(n) = freq(a(n-g(n)),n) where g = A000523 and freq(i, j) is the number of times i appears in the terms a(0) .. a(j-1).
4
0, 1, 1, 2, 2, 2, 3, 3, 3, 3, 4, 4, 4, 3, 3, 3, 3, 8, 8, 8, 8, 4, 4, 4, 4, 7, 7, 7, 7, 4, 4, 4, 4, 4, 12, 12, 12, 12, 12, 5, 5, 5, 5, 5, 5, 6, 6, 6, 6, 6, 5, 5, 5, 5, 5, 11, 11, 11, 11, 11, 5, 5, 5, 5, 5, 5, 17, 17, 17, 17, 17, 17, 6, 6, 6, 6, 6, 6, 11, 11, 11, 11, 11, 11, 11, 12, 12, 12, 12, 12, 12, 11, 11, 11, 11, 11
OFFSET
0,4
MAPLE
b:= proc() 0 end:
a:= proc(n) option remember; local t;
t:= `if`(n<2, n, b(a(n-ilog2(n))));
b(t):= b(t)+1; t
end:
seq(a(n), n=0..200); # Alois P. Heinz, Jul 26 2018
MATHEMATICA
c = <||>; f[n_] := If[KeyExistsQ[c, n], c[n], 0]; a[n_] := a[n] = Block[{v}, v = If[n < 2, n, f[a[n - Floor@ Log2@ n]]]; If[f[v] > 0, c[v] = c[v] + 1, c[v] = 1]; v]; Array[a, 96, 0] (* Giovanni Resta, Jul 26 2018 *)
CROSSREFS
KEYWORD
nonn,look
AUTHOR
Altug Alkan, Jul 26 2018
STATUS
approved