A172096 Primes having no representation of the form prime(n)-+n.
13, 17, 23, 31, 41, 47, 53, 59, 61, 67, 71, 73, 89, 97, 103, 107, 109, 131, 137, 151, 157, 167, 181, 191, 193, 199, 211, 227, 229, 233, 239, 241, 257, 263, 277, 281, 283, 293, 311, 313, 317, 331, 337, 347, 353, 359, 367, 379, 389
Offset: 1
Keywords
Examples
13 is a term because it's prime and prime(n)+n < 13 for n <= 4 and > 13 for n > 4, and prime(n)-n < 13 for n <= 8 and > 13 for n > 8.
Crossrefs
Cf. A064270.
Programs
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Mathematica
nn=100; p=Select[Union[Flatten[Table[Prime[n]+{-n,n}, {n,nn}]]], PrimeQ]; Complement[Prime[Range[PrimePi[p[[-1]]]]], p]
Extensions
Corrected by T. D. Noe, Nov 21 2010