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.

A272101 Square root of largest square dividing A069482(n).

Original entry on oeis.org

1, 4, 2, 6, 4, 2, 6, 2, 2, 2, 2, 2, 2, 6, 10, 4, 4, 16, 2, 12, 4, 18, 2, 4, 6, 2, 2, 12, 2, 4, 2, 2, 2, 24, 10, 2, 8, 2, 2, 8, 12, 2, 16, 2, 6, 2, 2, 30, 4, 2, 4, 8, 2, 2, 4, 2, 6, 2, 6, 2, 24, 20, 2, 4, 6, 36, 2, 6, 4, 6
Offset: 1

Views

Author

Benedict W. J. Irwin, Apr 20 2016

Keywords

Comments

Analogous to A001223 with 2-norm.
a(n) is the square root of the square part of A069482(n).

Examples

			sqrt(5)=1*sqrt(5), a(n)=1.
sqrt(16)=4*sqrt(1), a(n)=4.
sqrt(24)=2*sqrt(6), a(n)=2.
		

Crossrefs

Programs

  • Mathematica
    Table[Sqrt[Prime[n+1]^2-Prime[n]^2],{n,1,100}]/.Sqrt[_]->1
  • PARI
    a(n) = my(d=prime(n+1)^2 - prime(n)^2); sqrtint(d/core(d)); \\ Michel Marcus, Apr 27 2016

Formula

Conjectures: (Start)
a(A068361(n)) = A001223(A068361(n)).
a(A068361(n)) = 2 for n>1.
These are the only a(n)=A001223(n).
(End)
a(n) = A000188(A069482(n)). - Michel Marcus, Apr 27 2016