A174742 Smallest of three consecutive primes whose sum is not a prime.

2, 3, 13, 37, 43, 47, 59, 73, 89, 97, 103, 107, 113, 127, 131, 137, 151, 167, 173, 179, 181, 191, 193, 199, 223, 227, 233, 239, 241, 251, 257, 263, 269, 277, 307, 313, 317, 331, 353, 359, 367, 373, 383, 397, 419, 421, 433, 439, 443, 461, 479, 487, 503, 521, 523, 541, 557, 563, 569, 571, 577, 587, 593, 599, 601, 607, 613

Offset

1,1

Links

Table of n, a(n) for n=1..67.

Formula

A000040 \ A073681.

Mathematica

Prime[Select[Range[1000], ! PrimeQ[Prime[#] + Prime[# + 1] + Prime[# + 2]] &]]
Transpose[Select[Partition[Prime[Range[200]], 3, 1], !PrimeQ[ Total[#]]&]] [[1]] (* Harvey P. Dale, Jun 04 2013 *)

Prog

(Magma) [NthPrime(n): n in [1..150] | not IsPrime(NthPrime(n) + NthPrime(n+1) + NthPrime(n+2))]; // Vincenzo Librandi Mar 16 2020

Crossrefs

Cf. A073681.

Sequence in context: A169983 A151461 A228278 * A215279 A082539 A168483

Adjacent sequences: A174739 A174740 A174741 * A174743 A174744 A174745

Keyword

nonn

Author

Robert Wintner, Nov 30 2010

Status

approved