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%I #23 Aug 26 2015 12:21:45
%S 1,123,124,125,126,306,330,538,539,540,904,905,906,1147,1148,1149,
%T 1150,1346,1347,1348,1349,1350,1351,1352,1353,1354,1355,1356,1357,
%U 1358,1359,1360,1689,1690,1691,1692,1971,1972,2200,2201
%N Numbers n without prime numbers in the range (n-3*sqrt(sqrt(n)), n].
%C a(934) = 20831532 is probably the last term. Any further terms must be greater than 1.5 * 10^18. - _Charles R Greathouse IV_, Jun 27 2011
%H Charles R Greathouse IV, <a href="/A192231/b192231.txt">Table of n, a(n) for n = 1..934</a>
%e a(2)=123 because (123-3*sqrt(sqrt(123)), 123]=(123-9,9907.., 123]=(113,0092.., 123].
%t Select[Range[2000], PrimePi[# - 3Sqrt[Sqrt[#]]] == PrimePi[#] &] (* _Alonso del Arte_, Jun 27 2011 *)
%o (PARI) isA192231(n)=nextprime(floor(n+1-3*n^.25))>n \\ _Charles R Greathouse IV_, Jun 27 2011
%o (PARI) is(n)=for(k=0,sqrtnint(81*n-1,4),if(isprime(n-k), return(0))); 1 \\ _Charles R Greathouse IV_, Aug 26 2015
%Y Subsequence of A192226.
%Y Cf. A001223, A188817, A189025, A192926.
%K nonn
%O 1,2
%A _Juri-Stepan Gerasimov_, Jun 26 2011
%E a(2) added by Alonso del Arte, Jun 27 2011
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