cp's OEIS Frontend

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.

A094231 Lesser member p of sexy primes (p, p+6) such that (p+1, p+2, p+3, p+4, p+5) all have the same number of prime divisors (counted with multiplicity).

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%I A094231 #15 Sep 08 2022 08:45:13
%S A094231 601,42181,70201,240953,277493,414361,418793,619813,632147,637073,
%T A094231 723161,732233,739433,761393,781961,879001,934481,979201,1154233,
%U A094231 1320721,1327673,1357673,1611361,1685521,1866233,1877833,1950457
%N A094231 Lesser member p of sexy primes (p, p+6) such that (p+1, p+2, p+3, p+4, p+5) all have the same number of prime divisors (counted with multiplicity).
%H A094231 Amiram Eldar, <a href="/A094231/b094231.txt">Table of n, a(n) for n = 1..1000</a>
%e A094231 42181 is a term because 42181 and 42187 are sexy primes while 42182-42186 each have 4 prime divisors (counting multiplicity).
%t A094231 Select[Range[2*10^6],AllTrue[{#,#+6},PrimeQ]&&Length[Union[ PrimeOmega[ Range[ #+1,#+5]]]]==1&] (* The program uses the AllTrue function from Mathematica version 10 *) (* _Harvey P. Dale_, Dec 16 2015 *)
%o A094231 (Magma) f:=func<n|&+[p[2]: p in Factorization(n)]>; [p:p in PrimesUpTo(2000000)| IsPrime(p+6) and forall{k:k in [2..5]|f(p+k) eq f(p+1)} ]; // _Marius A. Burtea_, Dec 16 2019
%Y A094231 Cf. A023201, A046117.
%K A094231 easy,nonn
%O A094231 1,1
%A A094231 _Jason Earls_, May 29 2004