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1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 14, 15, 16, 17, 19, 21, 22, 23, 25, 26, 27, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 41, 42, 43, 46, 47, 49, 51, 53, 55, 57, 58, 59, 61, 62, 64, 65, 66, 67, 69, 70, 71, 73, 74, 77, 78, 79, 81, 82, 83, 85, 86, 87, 89, 90, 91, 93, 94, 95, 97, 100, 101, 102, 103, 105, 106, 107, 109, 110, 111, 113, 114, 115, 118, 119, 121, 122, 123, 125, 127, 128, 129, 130

isA360247 := proc(n)

local ifs, pidx, pe, meanAll, meanDist ;

if n = 1 then

return true ;

end if ;

ifs := ifactors(n)[2] ;

# list of prime indices with multiplicity

pidx := [] ;

for pe in ifs do

[numtheory[pi](op(1, pe)), op(2, pe)] ;

pidx := [op(pidx), %] ;

end do:

meanAll := add(op(1, pe)*op(2, pe), pe=pidx) / add(op(2, pe), pe=pidx) ;

meanDist := add(op(1, pe), pe=pidx) / nops(pidx) ;

if meanAll = meanDist then

true;

else

false;

end if;

end proc:

for n from 1 to 130 do

if isA360247(n) then

printf("%d, ", n) ;

end if;

end do: # R. J. Mathar, May 22 2023

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proposed

For multiplicities Signature instead of parts we have : A324570, counted by A114638.

For multiplicities Signature instead of distinct parts we have : A359903, counted by A360068.

A051293/A082550/A32747 count subsets with integer mean.

A088529/A088530 gives mean of prime signature (A124010).

A316413 list = numbers whose prime indices have integer mean, distinct A326621.

A360005 gives median of prime indices (times two).

Cf. A000975, A051293, A067340, A067538, `~A078174, `~A316313, ~`A326669, ~`A327475, `~A349156, ~`A360069, `A360005, A360241.

allocated Numbers for Gus Wisemanwhich the prime indices have the same mean as the distinct prime indices.

1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 14, 15, 16, 17, 19, 21, 22, 23, 25, 26, 27, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 41, 42, 43, 46, 47, 49, 51, 53, 55, 57, 58, 59, 61, 62, 64, 65, 66, 67, 69, 70, 71, 73, 74, 77, 78, 79, 81, 82, 83, 85, 86, 87, 89

1,2

First differs from A072774 in having 90.

First differs from A242414 in lacking 126.

Includes all squarefree numbers and perfect powers.

A prime index of n is a number m such that prime(m) divides n. The multiset of prime indices of n is row n of A112798.

The prime indices of 900 are {3,3,2,2,1,1} with mean 2, and the distinct prime indices are {1,2,3} also with mean 2, so 900 is in the sequence.

prix[n_]:=If[n==1, {}, Flatten[Cases[FactorInteger[n], {p_, k_}:>Table[PrimePi[p], {k}]]]];

Select[Range[100], Mean[prix[#]]==Mean[Union[prix[#]]]&]

For multiplicities instead of parts we have A324570, counted by A114638.

For multiplicities instead of distinct parts we have A359903, counted by A360068.

These partitions are counted by A360243.

The complement is A360246, counted by A360242.

For median instead of mean the complement is A360248, counted by A360244.

For median instead of mean we have A360249, counted by A360245.

For greater instead of equal mean we have A360252, counted by A360250.

For lesser instead of equal mean we have A360253, counted by A360251.

A008284 counts partitions by number of parts, distinct A116608.

A051293/A082550/A32747 count subsets with integer mean.

A058398 counts partitions by mean, also A327482.

A088529/A088530 gives mean of prime signature A124010.

A112798 lists prime indices, length A001222, sum A056239.

A316413 list numbers whose prime indices have integer mean, distinct A326621.

A326567/A326568 gives mean of prime indices.

A326619/A326620 gives mean of distinct prime indices.

A360005 gives median of prime indices (times two).

Cf. A000975, A067340, A067538, `~A078174, `~A316313, ~`A326669, ~`A327475, `~A349156, ~`A360069, `A360241.

allocated

nonn

Gus Wiseman, Feb 07 2023

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allocated for Gus Wiseman

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