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 A278583 Numbers k such that k+1 is a prime, k+2 is twice a prime, and k+3 is three times a prime. 5

%I

%S 12,36,156,540,876,1200,1380,1620,2016,2556,2856,3060,4356,4440,5076,

%T 5580,5700,6336,6636,6660,6996,7416,8220,9180,9660,9900,10836,11496,

%U 12456,12600,12720,12756,13680,14436,15240,16920,17076,18216,18300,18396,19440,21000,21576,22620,23556,24480

%N Numbers k such that k+1 is a prime, k+2 is twice a prime, and k+3 is three times a prime.

%C All terms are divisible by 12. - _Daniel Poveda Parrilla_, Dec 12 2016

%D R. K. Guy, Posting to Number Theory Mailing List, Nov 30 2016

%H Antti Karttunen and Charles R Greathouse IV, <a href="/A278583/b278583.txt">Table of n, a(n) for n = 1..10000</a> (first 563 terms from Antti Karttunen)

%o (PARI) list(lim)=my(v=List()); forprime(p=2,lim+1, if(p%6==1 && isprime(p\2+1) && isprime(p\3+1), listput(v,p-1))); Vec(v) \\ _Charles R Greathouse IV_, Dec 03 2016

%Y Equals A036570(n) - 1.

%Y Positions of terms >= 3 in A278500.

%Y Cf. A074200.

%K nonn

%O 1,1

%A _N. J. A. Sloane_, Nov 30 2016

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Last modified May 19 12:49 EDT 2019. Contains 323393 sequences. (Running on oeis4.)