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Strobogrammatic (A000787) composite numbers whose prime factors are strobogrammatic as well.
1

%I #5 Jul 08 2016 09:49:27

%S 1111,11088011,16169191,101808101,616101919,668808899,686808989,

%T 1016969101,1106699011,1199006611,6068888909,6699116699,6699886699,

%U 11990006611,16168089191,19190006161,19198086161,66110001199,66880008899,110668899011,161600009191

%N Strobogrammatic (A000787) composite numbers whose prime factors are strobogrammatic as well.

%C The smallest term which is the product of 3 primes is 1111008888001111 = 11 * 101 * 1000008000001. The smallest term which is not a multiple of 11 or 101 is a(790) = 100111801888108111001 = 100111001 * 1000008000001.

%H Giovanni Resta, <a href="/A274831/b274831.txt">Table of n, a(n) for n = 1..1000</a>

%e 16169191 is a term because it is equal to 101 * 160091.

%Y Cf. A000787, A007597.

%K nonn,base

%O 1,1

%A _G. L. Honaker, Jr._ and _Giovanni Resta_, Jul 08 2016