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Numbers k such that ceiling(k^1.5) is prime.
1

%I #10 Jul 04 2019 18:57:04

%S 2,7,8,11,13,14,15,17,19,21,28,29,31,34,41,54,57,71,82,83,92,96,98,

%T 102,104,108,124,130,140,142,145,147,148,156,158,171,206,213,223,231,

%U 233,240,252,254,255,261,262,266,267,275,284,297,299,300,315,322,343,354

%N Numbers k such that ceiling(k^1.5) is prime.

%e Ceiling(2^1.5) = 3, so 2 is in the sequence.

%e Ceiling(3^1.5) = 6, so 3 is not in the sequence.

%t Select[Range[400], PrimeQ[Ceiling[ #^(3/2)]]&]

%o (PARI) for (n=1,1000,if (isprime(ceil(n^1.5)),write("primes15n.txt",n)))

%Y The corresponding primes are in A070045.

%K nonn

%O 0,1

%A _Jon Perry_, May 03 2002

%E Edited by _Dean Hickerson_, May 07 2002