A178709 Position of start of first appearance of n consecutive 1's in the binary expansion of Pi.

3, 11, 11, 11, 11, 11, 451, 645, 645, 645, 5212, 18123, 18123, 58276, 58276, 80697, 80697, 80697, 1146746, 1962901, 3296306, 9772065, 9772065, 9772065, 47536571, 169338693, 169338693, 207861698, 207861698, 207861698

Offset

1,1

Comments

Out of the first 2^28 binary digits, 134220460 are "0" and 134214996 are "1". - Robert G. Wilson v, Jun 09 2010

This sequence ignores bits in the integer part of the binary expansion of Pi.

Links

Table of n, a(n) for n=1..30.

Example

6 consecutive 1's are first found beginning at the 11th position in Pi's binary expansion, so the sixth term in this sequence is 11.

Mathematica

pib = ToString@ FromDigits[ RealDigits[Pi - 3, 2, 2^28][[1]]]; f[n_] := 2 + StringPosition[ pib, ToString[(10^n - 1)/9], 1][[1, 1]]; Array[f, 30] (* Robert G. Wilson v, Jun 09 2010 *)

Crossrefs

Cf. A004601, A035117, A178708.

Sequence in context: A304052 A303122 A080351 * A168378 A248410 A059200

Adjacent sequences: A178706 A178707 A178708 * A178710 A178711 A178712

Keyword

base,nonn

Author

Will Nicholes, Jun 06 2010

Extensions

a(14)-a(30) from Robert G. Wilson v, Jun 09 2010

Status

approved