A211684 - OEIS

%I #15 Jun 28 2018 07:16:34

%S 1131,1137,1139,1271,1277,1311,1313,1317,1373,1379,1397,1491,1499,

%T 1571,1577,1631,1673,1677,1733,1739,1797,1811,1911,1919,1937,1971,

%U 1977,1991,1997,2113,2233,2239,2271,2277,2293,2331,2337,2397,2419,2571

%N Numbers > 1000 such that all the substrings of length = 3 are primes (substrings with leading '0' are considered to be nonprime).

%C Only numbers > 1000 are considered, since all 3-digit primes are trivial members. See A069489 for the sequence with prime terms > 1000.

%C The sequence is infinite (for example, consider the continued concatenation of '19' or of '337': 1919, 19191, 191919, ..., 3373, 33733, 337337, ... are members).

%C Infinitely many terms are palindromic.

%C A 10-automatic sequence realized by a linear recurrence relation. - _Charles R Greathouse IV_, Jan 04 2013

%H Hieronymus Fischer, <a href="/A211684/b211684.txt">Table of n, a(n) for n = 1..3000</a>

%H <a href="/index/Ar#10-automatic">Index entries for 10-automatic sequences</a>.

%e a(1) = 1131, since all substrings of length = 3 (113 and 131) are primes.

%e a(33) = 2271, since all substrings of length = 3 (227, 271) are primes.

%Y Cf. A019546, A035232, A039996, A046034, A069489, A085823, A211681, A211682.

%K nonn,base,easy

%O 1,1

%A _Hieronymus Fischer_, Jun 08 2012