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Revision History for A322902 (Underlined text is an addition; strikethrough text is a deletion.)

Showing all changes.
A322902 Numbers whose prime indices are all proper powers of the same number.
(history; published version)
#7 by Susanna Cuyler at Mon Dec 31 13:18:24 EST 2018
STATUS

proposed

approved

#6 by Gus Wiseman at Sun Dec 30 10:48:15 EST 2018
STATUS

editing

proposed

#5 by Gus Wiseman at Sun Dec 30 10:47:13 EST 2018
EXAMPLE

The Heinz number of an integer partition (y_1, ..., y_k) is prime(y_1) * ... * prime(y_k). The sequence of all integer partitions whose Heinz numbers belong to the sequence begins: (), (1), (2), (11), (3), (4), (111), (22), (5), (6), (1111), (7), (8), (42), (9), (33), (222).

#4 by Gus Wiseman at Sun Dec 30 09:29:28 EST 2018
COMMENTS

All termsAlso arethe oddunion orof powersA322903 ofand 2A000079.

CROSSREFS

Cf. A001597, A018819, A023893, A023894, A052410, A056239, A072720, A072721, A302242, A302593, A322900, A322901, A322903.

#3 by Gus Wiseman at Sun Dec 30 09:03:44 EST 2018
COMMENTS

A prime index of n is a number m such that prime(m) divides n.

A proper power of n is a number n^k for some positive integer k.

All terms are odd or powers of 2.

#2 by Gus Wiseman at Sun Dec 30 09:01:54 EST 2018
NAME

allocatedNumbers whose prime indices are all proper powers of forthe Gussame Wisemannumber.

DATA

1, 2, 3, 4, 5, 7, 8, 9, 11, 13, 16, 17, 19, 21, 23, 25, 27, 29, 31, 32, 37, 41, 43, 47, 49, 53, 57, 59, 61, 63, 64, 67, 71, 73, 79, 81, 83, 89, 97, 101, 103, 107, 109, 113, 115, 121, 125, 127, 128, 131, 133, 137, 139, 147, 149, 151, 157, 159, 163, 167, 169

OFFSET

1,2

EXAMPLE

The sequence of all integer partitions whose Heinz numbers belong to the sequence begins: (), (1), (2), (11), (3), (4), (111), (22), (5), (6), (1111), (7), (8), (42), (9), (33), (222).

MATHEMATICA

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

radbase[n_]:=n^(1/GCD@@FactorInteger[n][[All, 2]]);

Select[Range[100], SameQ@@radbase/@primeMS[#]&]

CROSSREFS

Cf. A001597, A018819, A023893, A023894, A052410, A056239, A072720, A072721, A302242, A302593, A322900, A322901.

KEYWORD

allocated

nonn

AUTHOR

Gus Wiseman, Dec 30 2018

STATUS

approved

editing

#1 by Gus Wiseman at Sun Dec 30 09:01:54 EST 2018
NAME

allocated for Gus Wiseman

KEYWORD

allocated

STATUS

approved

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Last modified August 29 06:09 EDT 2024. Contains 375510 sequences. (Running on oeis4.)