A215848 Primes > 3.

5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97, 101, 103, 107, 109, 113, 127, 131, 137, 139, 149, 151, 157, 163, 167, 173, 179, 181, 191, 193, 197, 199, 211, 223, 227, 229, 233, 239, 241, 251, 257, 263, 269, 271, 277, 281

Offset

1,1

Comments

Or, prime sums of primes (without repetition).

Or, smallest prime > n-th odd prime.

Or, primes p such that p*(p+1)/2-1 is a composite.

Note that p*(p+1)/2-1 = (1/2)*(p - 1)*(p + 2), also 3*(3+1)/2-1 = 5. - Joerg Arndt, Jan 12 2011.

The inclusion of this sequence in the OEIS is justified by the fact that a number of other sequences can be more simply described using it, and also so that Superseeker can make use of it. - N. J. A. Sloane, Aug 24 2012

Also level number where the total number of faces is increased by 4 in the perspective view of the stepped pyramid described in A245092. - Omar E. Pol, Mar 20 2019

Links

Table of n, a(n) for n=1..58.

Formula

a(n) = A000040(n+2). - Omar E. Pol, Mar 20 2019

Prog

(PARI) a(n)=prime(n+2) \\ Charles R Greathouse IV, Aug 26 2011
(PARI) vecextract(primes(52), "3..") \\ Charles R Greathouse IV, Aug 26 2011

Crossrefs

Cf. A000040, A237593, A245092.

Sequence in context: A171525 A140475 A171577 * A175212 A066047 A240710

Adjacent sequences: A215845 A215846 A215847 * A215849 A215850 A215851

Keyword

nonn,easy

Author

Juri-Stepan Gerasimov , Nov 29 2009

Extensions

Entries checked by R. J. Mathar, Mar 18 2010

Status

approved