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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A171179 Numbers that are divisible by exactly 3 primes (counted with multiplicity) and sandwiched between primes.

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%I A171179 #8 Jan 15 2024 13:37:02
%S A171179 12,18,30,42,102,138,282,618,642,822,1698,1878,2082,2238,2382,2658,
%T A171179 2802,3462,3558,3918,4638,4722,5442,6198,6702,8538,8598,9678,10938,
%U A171179 12162,12378,12822,12918,13218,13722,13758,13998,14082,16062,17418,19542
%N A171179 Numbers that are divisible by exactly 3 primes (counted with multiplicity) and sandwiched between primes.
%C A171179 There are 106 of these numbers below 10^5.
%e A171179 12 is a term: 12 = 2*2*3, and 11 and 13 primes.
%t A171179 Select[Range[9! ],Plus@@Last/@FactorInteger[ # ]==3&&PrimeQ[ #-1]&&PrimeQ[ #+1]&]
%Y A171179 Cf. A014612.
%Y A171179 Equals 6*A060212. - _Zak Seidov_ and _Esko Ranta_, Dec 06 2009
%K A171179 nonn
%O A171179 1,1
%A A171179 _Vladimir Joseph Stephan Orlovsky_, Dec 04 2009