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A052026 Composites base 10 that remain composite in all bases b, 2<=b<=10, expansions interpreted as decimal numbers. 19

%I

%S 14,18,20,24,30,32,36,40,42,44,51,54,60,62,69,70,72,74,76,78,80,86,90,

%T 92,96,98,99,100,102,104,108,110,112,114,120,124,125,126,128,129,130,

%U 132,135,140,144,146,148,150,152,156,158,159,160,162,164,168,170,174

%N Composites base 10 that remain composite in all bases b, 2<=b<=10, expansions interpreted as decimal numbers.

%H Sebastian Petzelberger, <a href="/A052026/b052026.txt">Table of n, a(n) for n = 1..10000</a>

%H Carlos Rivera, <a href="http://www.primepuzzles.net/puzzles/puzz_024.htm">PP&P Puzzle 24: Primes in several bases</a>

%t Select[Range@ 174, AllTrue[Table[FromDigits[IntegerDigits[#, i]], {i, 2, 10}], CompositeQ] &] (* _Michael De Vlieger_, Mar 24 2015, version 10 *)

%Y Cf. A052026, A038537, A052027-A052033, A084482, A236356

%K nonn,base

%O 1,1

%A _Patrick De Geest_, Dec 15 1999

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Last modified January 17 18:08 EST 2020. Contains 330987 sequences. (Running on oeis4.)