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A217265 Numbers with 4 or more prime factors (with multiplicity) such that every concatenation of their prime factors is prime. 4
21249, 33271, 89937, 146461, 147833, 148519, 164297, 175257, 211631, 216953, 234269, 254849, 261023, 269941, 311229, 318033, 348823, 377001, 390447, 520209, 561491, 848239, 941679, 943679, 957447, 960957, 1012879, 1110159, 1221431, 1410399, 1525203, 1681729 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..32.

EXAMPLE

21249 is 3*3*3*787. 333787, 337873, 378733 and 787333 are all prime, so 21249 is in the sequence.

CROSSREFS

Cf. A217263, A217264, A180679, A181559.

Sequence in context: A284915 A252165 A289674 * A236644 A178282 A234408

Adjacent sequences:  A217262 A217263 A217264 * A217266 A217267 A217268

KEYWORD

nonn,base

AUTHOR

Dmitri Kamenetsky, Sep 29 2012

STATUS

approved

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Last modified May 7 16:00 EDT 2021. Contains 343652 sequences. (Running on oeis4.)