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A318719 Heinz numbers of strict integer partitions in which no two parts are relatively prime. 16
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: A117289 A339817 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 May 14 04:40 EDT 2021. Contains 343872 sequences. (Running on oeis4.)