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%I #9 Jul 17 2022 07:38:11
%S 59,61,103,109,149,151,163,257,313,389,401,449,479,541,569,571,673,
%T 677,709,733,769,821,823,839,857,883,919,947,971,983,1061,1087,1093,
%U 1097,1129,1151,1163,1181,1249,1283,1301,1319,1321,1381,1433,1489,1493,1549
%N Primes p such that 2*p+-1 and 2*p+-3 are all composites.
%H Harvey P. Dale, <a href="/A172056/b172056.txt">Table of n, a(n) for n = 1..1000</a>
%e a(1)=59 because 2*59-1=117, 2*59+1=119, 2*59-3=115, 2*59+3=121 are all composites.
%t okQ[n_]:=Union[PrimeQ[{2n+1,2n-1,2n+3,2n-3}]]=={False}; Select[Prime[Range[250]],okQ] (* _Harvey P. Dale_, Feb 07 2010 *)
%t Select[Prime[Range[300]],AllTrue[2#+{1,3,-1,-3},CompositeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* _Harvey P. Dale_, Feb 20 2015 *)
%Y Cf. A000040, A002808, A068497.
%K nonn
%O 1,1
%A _Juri-Stepan Gerasimov_, Jan 24 2010
%E Corrected and extended by _Harvey P. Dale_, Feb 07 2010
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