A318719 - OEIS

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A318719

Heinz numbers of strict integer partitions in which no two parts are relatively prime.

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

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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 A369331

Adjacent sequences: A318716 A318717 A318718 * A318720 A318721 A318722

KEYWORD

nonn

AUTHOR

Gus Wiseman, Sep 02 2018

STATUS

approved