A180441 First term of four consecutive primes whose average is a prime

113, 131, 139, 173, 233, 421, 953, 1013, 1021, 1051, 1583, 1747, 1901, 2099, 2423, 2579, 2819, 2939, 3761, 3779, 3931, 4211, 4253, 4451, 4591, 5003, 5861, 5903, 6427, 6691, 6949, 7079, 7481, 7541, 7717, 8263, 8783, 8831, 9127, 9227, 9413, 9923, 10061

Offset

1,1

Links

Table of n, a(n) for n=1..43.

Formula

a(n)=[p(n)+p(n+1)+p(n+2)+p(n+3)]/4 a(n) being a prime

Example

a(5)=233 since (233+239+241+251)/4=964/4=241 is a prime.

Crossrefs

Cf. A000040, A122535

Sequence in context: A069488 A131648 A355856 * A180407 A163760 A179911

Adjacent sequences: A180438 A180439 A180440 * A180442 A180443 A180444

Keyword

nonn

Author

Carmine Suriano, Sep 05 2010

Status

approved