

A178709


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


1



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
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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: A038229 A257538 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



