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A282934 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. 2
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, 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, 3, 3, 3, 4, 1, 1, 2, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

LINKS

Table of n, a(n) for n=1..87.

EXAMPLE

Rows with power sets of set of divisors of n (without nonempty sets):

{1};

{1}, {2}, {1, 2};

{1}, {3}, {1, 3};

{1}, {2}, {4}, {1, 2}, {1, 4}, {2, 4}, {1, 2, 4};

...

Rows with the numbers of elements of these subsets:

1;

1, 1, 2;

1, 1, 2;

1, 1, 1, 2, 2, 2, 3;

...

Concatenation: 1, 1, 1, 2, 1, 1, 2, 1, 1, 1, 2, 2, 2, 3, ...

MATHEMATICA

Table[Length /@ Rest[Subsets[Divisors[n]]], {n, 1, 12}] // Flatten (* Jean-Fran├žois Alcover, Nov 13 2017 *)

CROSSREFS

Cf. A282903, A282935, A282936.

Sequence in context: A073203 A073204 A248641 * A273619 A034003 A168508

Adjacent sequences:  A282931 A282932 A282933 * A282935 A282936 A282937

KEYWORD

nonn

AUTHOR

Jaroslav Krizek, Feb 25 2017

STATUS

approved

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Last modified February 20 13:33 EST 2019. Contains 320327 sequences. (Running on oeis4.)