A008829 Smallest number a(n) formed from consecutive sequences of digits of Pi and satisfying a(n) > a(n-1); first 3 is omitted. (Formerly N1424)

1, 4, 15, 92, 653, 5897, 9323, 84626, 433832, 795028, 841971, 6939937, 51058209, 74944592, 307816406, 2862089986, 28034825342, 1170679821480, 8651328230664, 70938446095505, 82231725359408, 128481117450284, 1027019385211055

Offset

1,2

Comments

Terms are not permitted to start with a 0, so when this would otherwise occur the 0 must be included in the previous term, for example, a(18). - Sean A. Irvine, Apr 07 2018

References

N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).

Links

Sean A. Irvine, Table of n, a(n) for n = 1..250

Mathematica

pi = Rest@ RealDigits[Pi, 10, 2500][[1]]; a[0] = 0; a[n_] := a[n] = Block[{k = 1}, While[ FromDigits[ Take[pi, {1, k}]] < a[n - 1], k++]; While[ pi[[k + 1]] == 0, k++]; b = FromDigits[Take[pi, {1, k}]]; pi = Drop[pi, k]; b]; Array[a, 50] (* Robert G. Wilson v, Apr 08 2018 *)

Crossrefs

Cf. A000796. Apart from the two initial terms equals A016062.

Sequence in context: A076900 A346941 A081011 * A322920 A372730 A332533

Adjacent sequences: A008826 A008827 A008828 * A008830 A008831 A008832

Keyword

nonn,base

Author

N. J. A. Sloane. This sequence appeared in the 1973 "Handbook", but was then dropped from the database. Resubmitted by Victor H. Auerbach (vhambler(AT)voicenet.com). Entry revised by N. J. A. Sloane, Jun 11 2012

Extensions

a(19)-a(20) corrected and more terms from Sean A. Irvine, Apr 07 2018

Status

approved