|
| |
|
|
A068987
|
|
a(n) = first position in the digit sequence 3,1,4,1,5,9,.... of pi where the pattern "1,2,...,n" occurs.
|
|
1
| | |
|
|
|
OFFSET
| 1,1
|
|
|
COMMENTS
| 1. We may never know if a(n) is defined for all n. 2. We split up the digits of any number > 9 in the pattern, e.g. if n = 11, we search for the pattern "1,2,3,4,5,6,7,8,9,1,0,1,1". 3. The pattern "1,2,3,4,5,6" does not occur before the 100,000-th term in the digit sequence of Pi.
Here are two more terms: a(6) and a(7) were found via the referenced Pi-Search link, through which 100 million digits of pi are currently available. - Rick L. Shepherd (rshepherd2(AT)hotmail.com), Oct 10 2002
200 million digits now available at Pi-Search page. - Rick L. Shepherd (rshepherd2(AT)hotmail.com), Aug 06 2006
|
|
|
REFERENCES
| Waclaw Sierpinski: O stu prostych, ale trudnych zagadnieniach arytmetyki. Warsaw: PZWS, 1959, p. 32.
|
|
|
LINKS
| D. G. Andersen, The Pi-Search Page
|
|
|
MATHEMATICA
| p = ToString[N[Pi, 50000]/10]; t = {1, 12, 123, 1234, 12345}; g[n_] := StringPosition[p, ToString[n]][[1]][[1]] - 2; Table[g[t[[i]]], {i, 1, 5}]
|
|
|
CROSSREFS
| Sequence in context: A175974 A062596 A142415 * A141139 A141130 A157074
Adjacent sequences: A068984 A068985 A068986 * A068988 A068989 A068990
|
|
|
KEYWORD
| nonn,base
|
|
|
AUTHOR
| Joseph L. Pe (joseph_l_pe(AT)hotmail.com), Apr 01 2002
|
|
|
EXTENSIONS
| More terms from Rick L. Shepherd (rshepherd2(AT)hotmail.com), Oct 10 2002
a(8) from Rick L. Shepherd (rshepherd2(AT)hotmail.com), Aug 06 2006
|
| |
|
|
