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A163555 Composite numbers such that exactly three distinct permutations of digits give primes. 0
130, 136, 175, 176, 301, 310, 316, 361, 370, 371, 395, 398, 517, 539, 671, 703, 713, 715, 716, 730, 731, 893, 935, 938, 1004, 1025, 1027, 1034, 1040, 1043, 1052, 1058, 1072, 1085, 1118, 1124, 1142, 1147, 1169, 1174, 1189, 1196, 1198, 1205, 1207, 1214 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..46.

EXAMPLE

a(1) = 130 because 130 is composite and 13, 31, and 103 are prime permutations, and no other permutation of 130 is prime.

MATHEMATICA

With[{no=1400}, Select[Complement[Range[no], Prime[Range[PrimePi[no]]]], Count[FromDigits/@Permutations[IntegerDigits[#]], _?PrimeQ]==3&]]  (* Harvey P. Dale, Feb 25 2011 *)

CROSSREFS

Sequence in context: A250740 A025372 A045049 * A025373 A025364 A294311

Adjacent sequences:  A163552 A163553 A163554 * A163556 A163557 A163558

KEYWORD

easy,nonn,base

AUTHOR

Gil Broussard, Jul 30 2009

STATUS

approved

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Last modified July 23 16:14 EDT 2019. Contains 325258 sequences. (Running on oeis4.)