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.

A340469 First constant from family of prime-representing constants h_n (h1 = 1.2148208055...) such that ceiling(h_n) = prime(n).

Original entry on oeis.org

1, 2, 1, 4, 8, 2, 0, 8, 0, 5, 5, 2, 4, 3, 3, 3, 7, 4, 6, 9, 4, 5, 1, 3, 1, 2, 3, 4, 2, 2, 3, 7, 7, 0, 9, 5, 4, 2, 5, 9, 1, 5, 0, 2, 6, 0, 2, 1, 2, 2, 7, 2, 3, 9, 1, 5, 8, 0, 4, 1, 4, 6, 1, 9, 2, 9, 3, 8, 1, 3, 9, 9, 0, 9, 7, 9, 7, 6, 3, 2, 6, 0, 6, 0, 4, 0, 5, 9, 0, 6, 0, 3, 3, 3, 5, 5, 6, 2, 6, 5, 6, 3, 9, 0, 8
Offset: 1

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Author

Ilya Weinstein, Jan 08 2021

Keywords

Comments

The family of constants h_n (h1 = 1.2148208055...) for generation of the complete sequence of primes with using of a recursive relation for h_n such that ceiling(h_n) = prime(n). The recursive relation h_n = ceiling(h_{n-1})*(h_{n-1}-ceiling(h_{n-1})+2) generates the complete sequence of prime numbers. Constants h_n are irrational for all n.

Examples

			h1 = 1.21482080552433374694513123422377095425915026021227...
h2 = 2.42964161104866749389026246844754190851830052042454...
h3 = 4.28892483314600248167078740534262572555490156127363...
etc.
		

Crossrefs

Programs

  • Mathematica
    N[Sum[(Prime[k]-2)/Product[Prime[n],{n,1,k-1}],{k,1,150}],50]
  • PARI
    suminf(k=1, (prime(k)-2)/prod(i=1, k-1, prime(i))) \\ Michel Marcus, Jan 08 2021

Formula

h1 = Sum_{k>=1} (prime(k)-2)/Product_{i=1..k-1} prime(i).
Equals A249270 - A064648 - 1. - Antonio GraciĆ” Llorente, Dec 22 2023