A102821 Numbers n for which the square excess of n-th prime is prime.
2, 4, 5, 8, 9, 13, 14, 15, 19, 20, 23, 27, 28, 30, 35, 36, 37, 38, 39, 46, 49, 56, 57, 67, 68, 69, 71, 81, 83, 86, 93, 94, 96, 98, 107, 108, 109, 111, 112, 113, 114, 124, 128, 138, 139, 142, 144, 155, 156, 157, 158, 159, 160, 161, 162, 173, 178, 182, 192, 195, 196, 199
Offset: 0
Examples
7 - 2^2 = 3 is the square excess (see A056892) of 7 and it is prime. 7 is the 4th prime, so 4 is in the sequence.
Crossrefs
Cf. A056892.
Programs
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Mathematica
Select[Range[200],PrimeQ[Prime[#]-Floor[Sqrt[Prime[#]]]^2]&] (* Harvey P. Dale, Jul 06 2014 *)