A291927 Records transform of A218320.

1, 2, 3, 4, 5, 7, 9, 11, 15, 16, 20, 25, 27, 33, 36, 46, 50, 53, 77, 86, 118, 145, 158, 173, 174, 184, 224, 270, 282, 304, 330, 422, 522, 625, 656, 820, 881, 899, 1030, 1218, 1276, 1416, 1529, 1590, 1722, 2012, 2106, 2161, 2369, 2478, 2994, 3132, 3361, 3484

Offset

1,2

Links

Table of n, a(n) for n=1..54.

Example

A218320(n) for 1 <= n <= 24 is {1, 1, 1, 2, 1, 2, 1, 3, 2, 2, 1, 4, 1, 2, 2, 5, 1, 4, 1, 4, 2, 2, 1, 7}; the records are {1, 2, 3, 4, 5, 7}, thus these are the first 6 terms of this sequence.

Mathematica

f[n_, i_, t_] := f[n, i, t] = If[n == 1, 1, If[t == 1, Boole[n <= i], Sum[f[n/d, d, t - 1], {d, Select[Divisors@ n, # <= i &]}]]]; Union@ FoldList[Max, Array[f[#, #, 4] &, 10^5]] (* Michael De Vlieger, Sep 06 2017, after Alois P. Heinz at A218320 *)

Crossrefs

Cf. A033833, A218320.

Sequence in context: A279076 A076970 A064548 * A239497 A039850 A238486

Adjacent sequences: A291924 A291925 A291926 * A291928 A291929 A291930

Keyword

nonn

Author

Michael De Vlieger, Sep 06 2017

Status

approved