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%I #27 Aug 14 2013 19:10:53
%S 44,46,48,49,64,66,68,69,84,86,88,94,96,98,99,104,106,108,120,122,124,
%T 125,126,128,140,142,144,145,146,148,150,152,154,155,156,158,160,162,
%U 164,165,166,168,180,182,184,185,186,188,204,206,208,210,212,214,215
%N Composite numbers that remain composite if any digit is deleted (zero and one are not considered prime).
%C These are sometimes called "deletable composites".
%H T. D. Noe, <a href="/A225619/b225619.txt">Table of n, a(n) for n = 1..10000</a>
%H Dave Radcliffe, <a href="http://ideone.com/ul7Evh">Python program/code</a>
%e 142 is composite. If the 1 is deleted, 42 is composite. If the 4 is deleted, 12 is composite. If the 2 is deleted, 14 is composite. Therefore, 142 is included in this sequence.
%t prime01Q[n_] := n == 0 || n == 1 || PrimeQ[n]; okQ[n_] := Module[{d = IntegerDigits[n]}, Not[Or @@ prime01Q /@ Table[FromDigits[Delete[d, i]], {i, Length[d]}]]]; Select[Range[215], ! PrimeQ[#] && okQ[#] &] (* _T. D. Noe_, Aug 14 2013 *)
%Y Cf. A202262 (composite numbers in which all substrings are composite).
%K nonn,base,easy
%O 1,1
%A _Derek Orr_, Aug 04 2013
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