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.

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A095377 Values of k such that the total number of 1's in the binary expansions of the first k primes is a multiple of k.

Original entry on oeis.org

1, 4, 14, 43, 46, 141, 4900, 10264541, 10281244, 10281247, 10281248, 10281249, 10281266, 10281271, 10368575, 531439030, 1997778943, 412276655628
Offset: 1

Views

Author

Labos Elemer, Jun 07 2004

Keywords

Comments

Integer solutions to {A095375(x)/x is an integer}.
a(18) > pi(10^12). - Donovan Johnson, May 03 2010
a(20) > 6.2*10^11. The first 19 ratios between the total number of 1's and k are 1, 2, 3, 4, 4, 5, 8, 14, 14, 14, 14, 14, 14, 14, 14, 17, 18, 22. - Giovanni Resta, May 08 2017

Examples

			n=14: the relevant list = {2,3,5...,41,43} = {10,11,101,...,11001,11011} contains 42 digits "1", and 42/14 = 3, so 14 is in the sequence.
		

Crossrefs

Programs

  • Mathematica
    s=0; Reap[Do[s += DigitCount[Prime@n, 2][[1]]; If[Mod[s, n] == 0, Sow@ n], {n, 10^4}]][[2, 1]] (* Giovanni Resta, May 08 2017 *)

Formula

Integer solutions to {A095375(x)/x is an integer}.

Extensions

a(16)-a(17) from Donovan Johnson, May 03 2010
a(18) from Giovanni Resta, May 08 2017
Previous Showing 11-11 of 11 results.