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%I #13 Sep 23 2019 17:28:59
%S 1,1,1,4,9,48,211,1736,9777,91169,739174,8613817,83763730,1105436491,
%T 13222076337,207852246589,2789691577561,47759515531854,
%U 755158220565169,14595210284816038,255814560447492788,5373613110108953192,105867623217924984398,2460702471446564481641
%N 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 Wikipedia, <a href="https://en.wikipedia.org/wiki/Partition_(number_theory)">Partition (number theory)</a>
%e a(4) = 4:
%e 4 -> 31 -> 211 -> 1111
%e 4 -> 22 -> 1111
%e 4 -> 22 -> 112 -> 1111
%e 4 -> 22 -> 211 -> 1111
%Y Cf. A002846, A327643, A327697, A327698, A327702.
%K nonn
%O 1,4
%A _Alois P. Heinz_, Sep 22 2019
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