The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A217190 (Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
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A217190

a(n) is the number of digits in the decimal representation of the smallest power of 11 that contains n consecutive identical digits.
(history; published version)

#10 by Charles R Greathouse IV at Tue Apr 30 20:16:18 EDT 2013

STATUS

proposed

approved

#9 by V. Raman at Tue Apr 30 17:41:05 EDT 2013

STATUS

editing

proposed

#8 by V. Raman at Tue Apr 30 15:52:26 EDT 2013

EXTENSIONS

a(10)-a(13) added by V. Raman, Apr 30 2012, in correspondence with A215731.

#7 by V. Raman at Tue Apr 30 15:38:45 EDT 2013

EXTENSIONS

a(10)-a(13) added by V. Raman, Apr 30 2012 , in correspondence with A215731

#6 by V. Raman at Tue Apr 30 15:38:16 EDT 2013

DATA

1, 2, 9, 41, 163, 502, 1378, 3107, 9834, 41530, 223636, 308352, 308352

EXTENSIONS

a(10)-a(13) added by V. Raman, Apr 30 2012 in correspondence with A215731

STATUS

approved

editing

#5 by T. D. Noe at Wed Oct 03 14:46:25 EDT 2012

STATUS

editing

approved

#4 by T. D. Noe at Wed Oct 03 14:46:16 EDT 2012

MATHEMATICA

k = 0; Join[{1}, Table[While[d = IntegerDigits[11^k]; prt = Partition[Differences[d], n - 1, 1]; ! MemberQ[prt, Table[0, {n - 1}]], k++]; Length[d], {n, 2, 8}]] (* T. D. Noe, Oct 03 2012 *)

#3 by V. Raman at Mon Oct 01 07:45:50 EDT 2012

COMMENTS

Number of digits in 11^k is equal to ceilfloor(1 + k*log_10(11)).

#2 by V. Raman at Thu Sep 27 12:31:25 EDT 2012

NAME

allocated for V. Raman

a(n) is the number of digits in the decimal representation of the smallest power of 11 that contains n consecutive identical digits.

DATA

1, 2, 9, 41, 163, 502, 1378, 3107, 9834

OFFSET

1,2

COMMENTS

Number of digits in 11^k is equal to ceil(k*log_10(11)).

CROSSREFS

Cf. A215731, A215737.

KEYWORD

allocated

nonn,base

AUTHOR

V. Raman, Sep 27 2012

STATUS

approved

editing

#1 by V. Raman at Thu Sep 27 12:31:25 EDT 2012

NAME

allocated for V. Raman

KEYWORD

allocated

STATUS

approved