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.

A086171 Continued fraction of sum(prime(n)/10^b(n)), where b(n) = 1 + the total number of digits of the first n-1 primes, A068670.

Original entry on oeis.org

0, 4, 4, 6, 2, 5, 18, 1, 3, 4, 1, 2, 1, 2, 4, 7, 4, 1, 21, 2, 1, 3, 5, 2, 1, 1, 27, 1, 1, 5, 12, 1, 18, 1, 1, 1, 1, 1, 1, 9, 3, 1, 1, 1, 5, 1, 5, 2, 2, 1, 53, 1, 8, 1, 23, 6, 2, 2, 1, 1, 3, 1, 1, 25, 2, 2, 7, 1, 2, 3, 1, 4, 3, 12, 1, 2, 7, 1, 68, 1, 19, 1, 2, 2, 14, 4, 6, 2, 1, 2, 58, 2, 16, 1, 1, 1, 2, 2, 1
Offset: 1

Views

Author

Roger L. Bagula, Aug 26 2003

Keywords

Examples

			r=0.235811317192329313741434753596167717...
= 2/10^1 + 3/10^2 + 5/10^3 + 7/10^4 + 11/10^5 + 13/10^7 + ..., the exponents being increased by the length of the previous prime. - _M. F. Hasler_, Oct 17 2013
		

Programs

  • Mathematica
    (* number of powers of ten in the Primes as a sequence*) byte[n_Integer?Positive] := byte[n] =byte[n-1]+Floor[Log[Prime[n-1]]/Log[10]]+1 byte[0]=byte[1] = 1 b=Table[N[Prime[n]*10^(-byte[n]), Digits], {n, 1, Digits}] r=Apply[Plus, b]

Formula

r = sum_{n=1..infinity} prime(n)/10^b(n), where b(n+1)=b(n)+floor(log[10] prime(n))+1, b(1)=1. (Edited by M. F. Hasler, Oct 17 2013)

Extensions

Edited by M. F. Hasler, Oct 17 2013