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A247088 Primes sandwiched between 10-almost primes (A046314). 2

%I #19 Jul 05 2019 18:12:24

%S 3885569,5717249,8411201,9173249,11039489,13310081,13506751,13633759,

%T 14616449,15709951,17482879,21614849,21988097,24507521,24714559,

%U 26207551,26720767,28680319,30546559,31780351,32995999,33999103,34602751,38255489,38531249,38618369,40408831,44103041,44278001

%N Primes sandwiched between 10-almost primes (A046314).

%C Primes p such that p-1 and p+1 are 10-almost primes.

%H Zak Seidov, <a href="/A247088/b247088.txt">Table of n, a(n) for n = 1..1186</a>

%e 3885569 - 1 = 2^9 * 7589;

%e 3885569 + 1 = 2 * 3^6 * 5 * 13 * 41.

%t Select[Prime[Range[2678000]],PrimeOmega[#-1]==PrimeOmega[#+1]==10&] (* _Harvey P. Dale_, Jul 05 2019 *)

%o (PARI) is(n)=bigomega(n-1)==10 && bigomega(n+1)==10 && isprime(n) \\ _Charles R Greathouse IV_, Apr 27 2015

%Y Cf. A014612, A046314, A063644.

%K nonn

%O 1,1

%A _Zak Seidov_, Jan 10 2015

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Last modified May 1 17:02 EDT 2024. Contains 372175 sequences. (Running on oeis4.)