A179546 a(n) = p^2*(p + 3)/2, where p = prime(n).

10, 27, 100, 245, 847, 1352, 2890, 3971, 6877, 13456, 16337, 27380, 36982, 42527, 55225, 78652, 107911, 119072, 157115, 186517, 202502, 255881, 296227, 364366, 470450, 530452, 562277, 629695, 665336, 740602, 1048385, 1149787, 1313830

Offset

1,1

Comments

Old name was "The first a(n) numbers killed in a Sieve of Eratosthenes".

Links

Bruno Berselli, Table of n, a(n) for n = 1..1000

Formula

p^2*(p+3)/2 as p runs through the primes. [R. J. Mathar, Aug 05 2010]

Example

2:  2*2 + 2*3 = 2*(3*4/2-1) = 10;
3:  3*2 + 3*3 + 3*4 = 3*(4*5/2-1) = 27;
5:  5*2 + 5*3 + 5*4 + 5*5 + 5*6 = 5*(6*7/2-1) = 100;
7:  7*2 + 7*3 + 7*4 + 7*5 + 7*6 + 7*7 + 7*8 = 7*(8*9/2-1) = 245; etc.

Mathematica

Table[Prime[n]^2 (Prime[n] + 3)/2, {n, 40}] (* Bruno Berselli, Feb 03 2015 *)
#^2 (#+3)/2&/@Prime[Range[40]] (* Harvey P. Dale, Feb 23 2018 *)

Prog

(PARI) vector(50, n, p=prime(n); p^2*(p+3)/2) \\ Michel Marcus, Feb 03 2015
(Magma) [p^2*(p+3)/2: p in PrimesUpTo(200)]; // Bruno Berselli, Feb 03 2015

Crossrefs

Cf. A000040.

Sequence in context: A220021 A008468 A267217 * A119548 A219629 A262316

Adjacent sequences: A179543 A179544 A179545 * A179547 A179548 A179549

Keyword

nonn

Author

Odimar Fabeny, Jul 19 2010

Extensions

More terms from R. J. Mathar, Aug 05 2010

Name and example rephrased and offset changed by Editors of the OEIS, Feb 03 2015

Status

approved