cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A046731 a(n) = sum of primes < 10^n.

Original entry on oeis.org

0, 17, 1060, 76127, 5736396, 454396537, 37550402023, 3203324994356, 279209790387276, 24739512092254535, 2220822432581729238, 201467077743744681014, 18435588552550705911377, 1699246443377779418889494, 157589260710736940541561021, 14692398516908006398225702366
Offset: 0

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Keywords

Comments

a(21) was already correctly computed by Marc Deleglise in 2009 but in 2011 he withdrew his result because his verification failed. - Kim Walisch, Jun 06 2016

Examples

			The primes less than 10 give 2+3+5+7 = 17.
		

Crossrefs

Cf. A034387.

Programs

  • Mathematica
    Join[{0, s = 17}, Table[Do[If[PrimeQ[i], s += i], {i, 10^n + 1, 10^(n + 1), 2}]; s, {n, 7}]] (* Jayanta Basu, Jun 28 2013 *)
    Table[Sum[Prime[i], {i, PrimePi[10^n]}], {n, 0, 7}]  (* Kim Walisch, Dec 21 2017 *)
  • PARI
    a(n) = my(s=0); forprime(p=1, 10^n, s += p); s; \\ Michel Marcus, Jan 14 2015
    
  • Perl
    use ntheory ":all"; say "$ ",sum_primes(10**$) for 0..15; # Dana Jacobsen, May 04 2017

Formula

a(n) is about 100^n/(n log 100). - Charles R Greathouse IV, Jan 29 2013
a(n) = Sum_{i=2..10^n} A061397(i). - José de Jesús Camacho Medina, Aug 08 2016

Extensions

Corrected and extended by Jud McCranie
a(12) and a(13) from Cino Hilliard, Aug 14 2006
New value for a(13) from Cino Hilliard, Oct 24 2007
There was indeed an error in a(13) both in the entry here and in the b-file. This has now been corrected. - N. J. A. Sloane, Nov 23 2007
Two new values from Marc Deleglise, May 21 2008 - see the b-file.
a(21) from Marc Deleglise, Jun 29 2008 - see the b-file.
Nov 15 2011: Marc Deleglise has withdrawn his value for a(21).
a(21)-a(22) from Kim Walisch, Jun 06 2016
a(23) from Kim Walisch, Jun 11 2016
a(24) from David Baugh using Kim Walisch's primesum program, Jun 17 2016
a(25) from David Baugh using Kim Walisch's primesum program, Oct 16 2016
a(26) from Kim Walisch, May 25 2022, added by Lorenzo Pieri