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A318719 Heinz numbers of strict integer partitions in which no two parts are relatively prime. 6
1, 2, 3, 5, 7, 11, 13, 17, 19, 21, 23, 29, 31, 37, 39, 41, 43, 47, 53, 57, 59, 61, 65, 67, 71, 73, 79, 83, 87, 89, 91, 97, 101, 103, 107, 109, 111, 113, 115, 127, 129, 131, 133, 137, 139, 149, 151, 157, 159, 163, 167, 173, 179, 181, 183, 185, 191, 193, 197 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

The Heinz number of an integer partition (y_1, ..., y_k) is prime(y_1) * ... * prime(y_k).

LINKS

Table of n, a(n) for n=1..59.

MATHEMATICA

Select[Range[200], And[SquareFreeQ[#], And@@(GCD[##]>1&)@@@Select[Tuples[PrimePi/@FactorInteger[#][[All, 1]], 2], Less@@#&]]&]

CROSSREFS

Cf. A302797, A303140, A303282, A303283, A305713, A305843, A318717, A318715, A318716, A318717.

Sequence in context: A230606 A117289 A328513 * A106317 A246281 A152242

Adjacent sequences:  A318716 A318717 A318718 * A318720 A318721 A318722

KEYWORD

nonn

AUTHOR

Gus Wiseman, Sep 02 2018

STATUS

approved

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Last modified April 1 05:04 EDT 2020. Contains 333155 sequences. (Running on oeis4.)