cp's OEIS Frontend

A327699 Number of refinement sequences n -> ... -> {1}^n, where in each step every single part of a nonempty selection of parts is replaced by a partition of itself into two smaller parts (in weakly decreasing order).

%I A327699 #13 Sep 23 2019 17:28:59
%S A327699 1,1,1,4,9,48,211,1736,9777,91169,739174,8613817,83763730,1105436491,
%T A327699 13222076337,207852246589,2789691577561,47759515531854,
%U A327699 755158220565169,14595210284816038,255814560447492788,5373613110108953192,105867623217924984398,2460702471446564481641
%N A327699 Number of refinement sequences n -> ... -> {1}^n, where in each step every single part of a nonempty selection of parts is replaced by a partition of itself into two smaller parts (in weakly decreasing order).
%H A327699 Wikipedia, <a href="https://en.wikipedia.org/wiki/Partition_(number_theory)">Partition (number theory)</a>
%e A327699 a(4) = 4:
%e A327699   4 -> 31   -> 211  -> 1111
%e A327699   4 -> 22   -> 1111
%e A327699   4 -> 22   -> 112  -> 1111
%e A327699   4 -> 22   -> 211  -> 1111
%Y A327699 Cf. A002846, A327643, A327697, A327698, A327702.
%K A327699 nonn
%O A327699 1,4
%A A327699 _Alois P. Heinz_, Sep 22 2019