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.

A098324 Recurrence sequence based on positions of digits in decimal places of phi, the Golden Ratio = (1+sqrt(5))/2.

Original entry on oeis.org

0, 4, 11, 34, 26, 67, 150, 1485, 2497, 8001, 2773, 16668, 39567, 80705, 15643, 19267, 29310, 223602, 2318795, 9376463, 7972671, 2412975, 3754694, 9560425, 1910435
Offset: 0

Views

Author

Mark Hudson (mrmarkhudson(AT)hotmail.com), Sep 03 2004

Keywords

Examples

			phi=1.61803398874989484820...
So for example, a(2)=4 because 4th decimal place of phi is 0.
a(3)=11 because 11th decimal place of phi is 4, a(4)=34 because 11 appears at the 34th to 35th decimal places and so on.
		

Crossrefs

Other recurrence sequences: A097614 for Pi, A098266 for e, A098289 for log(2), A098290 for Zeta(3), A098319 for 1/Pi, A098320 for 1/e, A098321 for gamma, A098322 for G, A098323 for 1/G.

Programs

  • Maple
    with(StringTools): Digits:=100000: G:=convert(evalf((1+sqrt(5))/2),string): a[0]:=0: for n from 1 to 17 do a[n]:=Search(convert(a[n-1],string), G)-2:printf("%d, ",a[n-1]):od: # Nathaniel Johnston, Apr 30 2011

Formula

a(1)=0, p(i)=position of first occurrence of a(i) in decimal places of phi, a(i+1)=p(i).

Extensions

a(17)-a(24) from Nathaniel Johnston, Apr 30 2011