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%I #11 Sep 01 2012 09:10:52
%S 1002,1003,1005,1007,1009,1010,1014,1016,1018,1020,1024,1026,1028,
%T 1041,1042,1045,1049,1050,1054,1056,1058,1062,1065,1069,1082,1085,
%U 1089,1090,1094,1096,1098,1099,1100,1104,1106,1108,1140,1144,1146,1148
%N Numbers with exactly 9 nonprime substrings (substrings with leading zeros are considered to be nonprime).
%C The sequence is finite. Proof: Each 8-digit number has at least 10 nonprime substrings. Thus each number with more than 8 digits has >= 10 nonprime substrings, too. Consequently there is a boundary b<10^7 such that all numbers > b have more than 9 nonprime substrings.
%C The first term is a(1) = 1002 = A213302(9). The last term is a(12411) = 9973331 = A213300(9).
%H Hieronymus Fischer, <a href="/A213316/b213316.txt">Table of n, a(n) for n = 1..12411</a>
%e a(1) = 1002 is in the sequence, since 1002 has 9 nonprime substrings (0, 0, 1, 00, 02, 10, 002, 100, 1002).
%e a(12411) = 9973331 is in the sequence since there are 9 nonprime substrings (1, 9, 9, 33, 33, 99, 333, 973, 97333).
%Y Cf. A019546, A035232, A039996, A046034, A069489, A085823, A211681, A211682, A211684, A211685.
%Y Cf. A035244, A079307, A213300 - A213321.
%K nonn,base,fini
%O 1,1
%A _Hieronymus Fischer_, Aug 26 2012
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