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A285690 a(1) = 2; a(n + 1) = smallest prime > a(n) such that a(n + 1) - a(n) is the product of five primes. 5

%I

%S 2,569,601,673,853,1021,1069,1117,1229,1277,1439,1471,1543,1663,1783,

%T 1831,1879,1951,1999,2111,2143,2251,2371,2539,2647,2719,2767,2879,

%U 2927,2999,3079,3187,3259,3307,3469,3517,3637,3709,3821,3853,4021,4093,4201

%N a(1) = 2; a(n + 1) = smallest prime > a(n) such that a(n + 1) - a(n) is the product of five primes.

%C First differences: 567, 32, 72, 180, 168, 48, 48, 112, 48, 162, 32, 72, 120, 120, 48, 48, 72, 48, 112, 32, ...

%H Robert Israel, <a href="/A285690/b285690.txt">Table of n, a(n) for n = 1..10000</a>

%p A[1]:= 2:

%p for n from 2 to 100 do

%p p:= A[n-1];

%p do

%p p:= nextprime(p);

%p if numtheory:-bigomega(p-A[n-1])=5 then A[n]:= p; break fi

%p od od:

%p seq(A[i],i=1..100); # _Robert Israel_, Nov 04 2019

%t NestList[Module[{p = NextPrime@ #}, While[PrimeOmega[p - #] != 5, p = NextPrime@ p]; p] &, 2, 40] (* _Michael De Vlieger_, Apr 25 2017 *)

%Y Cf. A255609, A285688, A285689.

%K nonn

%O 1,1

%A _Zak Seidov_, Apr 24 2017

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Last modified November 26 21:07 EST 2021. Contains 349344 sequences. (Running on oeis4.)