|
%I #8 Nov 13 2017 03:01:57
%S 1,1,1,2,1,1,2,1,1,1,2,2,2,3,1,1,2,1,1,1,1,2,2,2,2,2,2,3,3,3,3,4,1,1,
%T 2,1,1,1,1,2,2,2,2,2,2,3,3,3,3,4,1,1,1,2,2,2,3,1,1,1,1,2,2,2,2,2,2,3,
%U 3,3,3,4,1,1,2,1,1,1,1,1,1,2,2,2,2,2,2
%N Concatenation of the numbers of elements of P{d_1}, P{d_2}, P{d_3}, ..., P{d_n}; where P{d_n} denote the power set of the set of divisors of n ordered by the size of the subsets, and in each subset, following the increasing order.
%e Rows with power sets of set of divisors of n (without nonempty sets):
%e {1};
%e {1}, {2}, {1, 2};
%e {1}, {3}, {1, 3};
%e {1}, {2}, {4}, {1, 2}, {1, 4}, {2, 4}, {1, 2, 4};
%e ...
%e Rows with the numbers of elements of these subsets:
%e 1;
%e 1, 1, 2;
%e 1, 1, 2;
%e 1, 1, 1, 2, 2, 2, 3;
%e ...
%e Concatenation: 1, 1, 1, 2, 1, 1, 2, 1, 1, 1, 2, 2, 2, 3, ...
%t Table[Length /@ Rest[Subsets[Divisors[n]]], {n, 1, 12}] // Flatten (* _Jean-François Alcover_, Nov 13 2017 *)
%Y Cf. A282903, A282935, A282936.
%K nonn
%O 1,4
%A _Jaroslav Krizek_, Feb 25 2017
|
