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A052054 Composite numbers all of whose prime factors (considered with multiplicity) share at least one digit. 1
4, 8, 9, 16, 25, 27, 32, 39, 46, 49, 58, 64, 69, 81, 92, 93, 111, 116, 117, 119, 121, 125, 128, 129, 143, 159, 169, 184, 187, 207, 209, 219, 221, 232, 243, 247, 249, 254, 256, 259, 265, 279, 289, 295, 299, 309, 323, 329, 333, 339, 341, 343, 351, 361, 368, 387 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..56.

EXAMPLE

E.g., 92 = 2 * 2 * 23 is a term because the sets {2}, {2} and {2,3} share the digit 2.

MATHEMATICA

Select[2~Range~500, !PrimeQ@#&&And@@IntersectingQ@@@Subsets[ IntegerDigits[ First/@FactorInteger[#]], {2}]&] (* Giorgos Kalogeropoulos, May 09 2019 *)

CROSSREFS

Cf. A052053.

Sequence in context: A090515 A075309 A175031 * A046447 A087244 A080062

Adjacent sequences:  A052051 A052052 A052053 * A052055 A052056 A052057

KEYWORD

nonn,base

AUTHOR

Patrick De Geest, Dec 15 1999

EXTENSIONS

Offset 1 from Michel Marcus, May 09 2019

Name clarified by Jon E. Schoenfield, May 10 2019

STATUS

approved

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Last modified June 16 21:13 EDT 2019. Contains 324155 sequences. (Running on oeis4.)