A155912 Let d(i) be the i-th digit of the decimal expansion of Pi = 3.1415926535897932384626433832795..., so that d(0) = 3, d(1) = 1, d(2) = 4, etc. Then a(0) = 3, a(n) = d(d(n)) for n>0.

3, 1, 5, 1, 9, 3, 4, 2, 9, 1, 9, 5, 3, 6, 3, 1, 4, 1, 5, 5, 2, 4, 2, 5, 1, 1, 5, 1, 4, 6, 3, 9, 3, 4, 5, 5, 5, 1, 3, 6, 1, 2, 3, 1, 3, 3, 1, 6, 9, 1, 3, 9, 5, 4, 3, 3, 6, 5, 3, 5, 5, 9, 3, 4, 1, 3, 6, 5, 1, 2, 5, 3, 2, 4, 5, 2, 4, 3, 5, 3, 3, 5, 2, 4, 5, 3, 1, 5, 5, 4, 9, 1, 5, 4, 1, 1, 6, 3, 2, 6, 3, 5, 4, 1, 5

Offset

0,1

Comments

This defines a constant 3.151934291953631... related to Pi in a peculiar way!

Links

Zak Seidov, Table of n, a(n) for n = 0..999

Mathematica

id = Rest@ RealDigits[ Pi, 10, 105][[1]]; id[[0]] = 3; id[[ id[[ 0]]]] = 3; Table[id[[ id[[ n]]]], {n, 0, 104}] (* Robert G. Wilson v, Mar 17 2009 *)

Crossrefs

Cf. A135725.

Cf. A119505. - Robert G. Wilson v, Mar 17 2009

Sequence in context: A302787 A240535 A262397 * A050354 A146434 A126213

Adjacent sequences: A155909 A155910 A155911 * A155913 A155914 A155915

Keyword

nonn,base

Author

Dan Brown (ddbhockey(AT)hotmail.com), Jan 30 2009

Extensions

Edited and extended by Zak Seidov and N. J. A. Sloane, Feb 10 2009

Sequence corrected by N. J. A. Sloane Aug 31 2009 using terms from the b-file

Status

approved